The Old Red Sandstone is an assemblage of rocks in the North Atlantic region largely of

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, wh ...

age. It extends in the east across Great Britain, Ireland and Norway, and in the west along the northeastern seaboard of

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...

. It also extends northwards into

Greenland Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland ...

and

Svalbard Svalbard ( , ), also known as Spitsbergen, or Spitzbergen, is a Norwegian archipelago in the Arctic Ocean. North of mainland Europe, it is about midway between the northern coast of Norway and the North Pole. The islands of the group rang ...

. These areas were a part of the ancient

continent A continent is any of several large landmasses. Generally identified by convention rather than any strict criteria, up to seven geographical regions are commonly regarded as continents. Ordered from largest in area to smallest, these seven ...

of Euramerica/Laurussia. In Britain it is a lithostratigraphic unit (a sequence of

rock strata In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as e ...

) to which stratigraphers accord supergroup status and which is of considerable importance to early

paleontology Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...

. For convenience the short version of the term, ORS is often used in literature on the subject. The term was coined to distinguish the sequence from the younger

New Red Sandstone The New Red Sandstone, chiefly in British geology, is composed of beds of red sandstone and associated rocks laid down throughout the Permian (300 million years ago) to the end of the Triassic (about 200 million years ago), that under ...

which also occurs widely throughout Britain.

Sedimentology

The Old Red Sandstone describes a suite of

sedimentary Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...

rocks deposited in a variety of environments during the

but extending back into the late

Silurian The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleoz ...

and on into the earliest part of the

Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carboniferou ...

. The body of rock, or

facies In geology, a facies ( , ; same pronunciation and spelling in the plural) is a body of rock with specified characteristics, which can be any observable attribute of rocks (such as their overall appearance, composition, or condition of formatio ...

, is dominated by

alluvial Alluvium (from Latin ''alluvius'', from ''alluere'' 'to wash against') is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings. ...

sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand ...

s and conglomerates at its base, and progresses to a combination of

dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, f ...

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

s and

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of ...

sediments. The familiar red colour of these rocks arises from the presence of

iron oxide Iron oxides are chemical compounds composed of iron and oxygen. Several iron oxides are recognized. All are black magnetic solids. Often they are non-stoichiometric. Oxyhydroxides are a related class of compounds, perhaps the best known of wh ...

but not all the Old Red Sandstone is red or sandstone — the sequence also includes conglomerates, mudstones, siltstones and thin limestones and colours can range from grey and green through to red and purple. These deposits are closely associated with the erosion of the Caledonian Mountain chain which was thrown up by the collision of the former continents of Avalonia, Baltica and

Laurentia Laurentia or the North American Craton is a large continental craton that forms the ancient geological core of North America. Many times in its past, Laurentia has been a separate continent, as it is now in the form of North America, althoug ...

to form the Old Red Sandstone Continent- an event known as the Caledonian Orogeny. Many fossils are found within the rocks, including early fishes, arthropods and plants. As is typical with terrestrial red beds, the vast majority of the rock is unfossiliferous; however there are isolated, localized beds within the rock that do contain fossils. Rocks of this age were also laid down in

South West England South West England, or the South West of England, is one of nine official regions of England. It consists of the counties of Bristol, Cornwall (including the Isles of Scilly), Dorset, Devon, Gloucestershire, Somerset and Wiltshire. Cities ...

(hence the name 'Devonian'; from

Devon Devon ( , historically known as Devonshire , ) is a ceremonial and non-metropolitan county in South West England. The most populous settlement in Devon is the city of Plymouth, followed by Devon's county town, the city of Exeter. Devo ...

) though these are of true marine origin and are not included within the Old Red Sandstone.

Stratigraphy

Since the Old Red Sandstone consists predominantly of rocks of terrestrial origin, it does not generally contain marine

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s which would otherwise prove useful in correlating one occurrence of the rock with another, both between and within individual

sedimentary basin Sedimentary basins are region-scale depressions of the Earth's crust where subsidence has occurred and a thick sequence of sediments have accumulated to form a large three-dimensional body of sedimentary rock. They form when long-term subsiden ...

s. Accordingly, local stage names were devised and these remain in use to some extent today though there is an increasing use of international stage names. Thus in the Anglo-Welsh Basin, there are frequent references to the Downtonian, Dittonian, Breconian and Farlovian stages in the literature. The existence of a number of distinct sedimentary basins throughout Britain has been established.

Orcadian Basin

The

Orcadian Basin The Orcadian Basin is a sedimentary basin of Devonian age that formed mainly as a result of extensional tectonics in northeastern Scotland after the end of the Caledonian orogeny. During part of its history, the basin was filled by a lake now known ...

extends over a wide area of North East Scotland and the neighbouring seas. It encompasses the

Moray Firth The Moray Firth (; Scottish Gaelic: ''An Cuan Moireach'', ''Linne Mhoireibh'' or ''Caolas Mhoireibh'') is a roughly triangular inlet (or firth) of the North Sea, north and east of Inverness, which is in the Highland council area of north of Sc ...

and adjoining land areas, Caithness, Orkney and parts of

Shetland Shetland, also called the Shetland Islands and formerly Zetland, is a subarctic archipelago in Scotland lying between Orkney, the Faroe Islands and Norway. It is the northernmost region of the United Kingdom. The islands lie about to the n ...

. South of the Moray Firth, two distinct sub-basins are recognised at Turriff and at Rhynie. The sequence is more than thick in parts of Shetland. The main basin is considered to be an intramontane basin resulting from crustal rifting associated with post-Caledonian

extension Extension, extend or extended may refer to: Mathematics Logic or set theory * Axiom of extensionality * Extensible cardinal * Extension (model theory) * Extension (predicate logic), the set of tuples of values that satisfy the predicate * Ext ...

, possibly accompanied by strike-slip faulting along the Great Glen Fault system.

Argyll

There are a scatter of exposures of the Old Red Sandstone around Oban and the Isle of Kerrera on the West Highland coast, this unit is sometimes referred to as the Kerrera Sandstone Formation. The unit is up to 128m thick in its type area and consists of green and red sandstones and conglomerates, typically containing large ( across) elliptical well rounded clasts, accompanied by siltstones, mudstones and limestones. On Kerrera a conglomerate of

andesite Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predo ...

boulders rests unconformably on

Dalradian The Dalradian Supergroup (informally and traditionally the Dalradian) is a stratigraphic unit (a sequence of rock strata) in the lithostratigraphy of the Grampian Highlands of Scotland and in the north and west of Ireland. The diverse assembl ...

black, pyritic slates (

Easdale Easdale ( gd, Eilean Èisdeal) is one of the Slate Islands, in the Firth of Lorn, Scotland. Once the centre of the Scottish slate industry, there has been some recent island regeneration by the owners. This is the smallest of the Inner Hebrides' ...

Slate) of the Easdale Subgroup. On Oban there is merely an erosional contact incorporating debris of the slate in a basal conglomerate. The ORS around Oban are considered latest

( Pridoli) to earliest Devonian in age. They are interpreted as alluvial fans which filled a depositional basin from the east and northeast. Small outliers occur near Taynuilt and either side of Loch Avich. The deposits are especially obvious on

Kerrera Kerrera (; gd, Cearara or ''Cearrara'') is an island in the Scottish Inner Hebrides, close to the town of Oban. In 2016 it had a population of 45, divided into two communities in the north and south of the island. Geology The oldest bedrock ...

where they form the bedrock across half of the island. These are conformably overlain by

peperite A peperite is a type of volcaniclastic rock consisting of sedimentary rock that contains fragments of younger igneous material and is formed when magma comes into contact with wet sediments. The term was originally used to describe rocks from th ...

and the

basalt Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90 ...

ic and andesitic

Lorne plateau lavas The Lorne plateau lavas are basaltic lava flows extruded in the late Silurian, 424 to 415 million years ago, which are found today in the Oban - Kerrera area of Scotland. Peperite occurs where they flowed into Old Red Sandstone The Old Red Sa ...

. The ORS on Kerrera and isolated localities around Oban are known for their fossils, particularly fish. Gardenstown Old Red Sandstone - geograph

Midland Valley of Scotland

The Midland Valley

graben In geology, a graben () is a depressed block of the crust of a planet or moon, bordered by parallel normal faults. Etymology ''Graben'' is a loan word from German, meaning 'ditch' or 'trench'. The word was first used in the geologic conte ...

defined by the Highland Boundary Fault in the north and the Southern Uplands Fault in the south harbours not only a considerable amount of Old Red Sandstone sedimentary rocks but also igneous rocks of this age associated with extensive

volcanism Volcanism, vulcanism or volcanicity is the phenomenon of eruption of molten rock (magma) onto the surface of the Earth or a solid-surface planet or moon, where lava, pyroclastics, and volcanic gases erupt through a break in the surface called a ...

. There is a continuous outcrop along the Highland Boundary Fault from Stonehaven on the

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian ...

coast to Helensburgh and beyond to Arran. A more disconnected series of outcrops occur along the line of the Southern Uplands Fault from

Edinburgh Edinburgh ( ; gd, Dùn Èideann ) is the capital city of Scotland and one of its 32 Council areas of Scotland, council areas. Historically part of the county of Midlothian (interchangeably Edinburghshire before 1921), it is located in Lothian ...

to Girvan. Old Red Sandstone often occurs in conjunction with conglomerate formations, one such noteworthy

cliff In geography and geology, a cliff is an area of rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. Cliffs are common on co ...

side exposure being the

Fowlsheugh Nature Reserve Fowlsheugh is a coastal nature reserve in Kincardineshire, northeast Scotland, known for its cliff formations and habitat supporting prolific seabird nesting colonies. Designated as a Site of Special Scientific Interest (SSSI) by Scottish Natura ...

, Kincardineshire.

Scottish borders

A series of outcrops occur from East Lothian southwards through

Berwickshire Berwickshire ( gd, Siorrachd Bhearaig) is a historic county, registration county and lieutenancy area in south-eastern Scotland, on the English border. Berwickshire County Council existed from 1890 until 1975, when the area became part of th ...

. Hutton's famous unconformity at Siccar Point occurs within this basin - see History of study below.

Anglo-Welsh Basin

This relatively large basin extends across much of South Wales from southern

Pembrokeshire Pembrokeshire ( ; cy, Sir Benfro ) is a county in the south-west of Wales. It is bordered by Carmarthenshire to the east, Ceredigion to the northeast, and the rest by sea. The county is home to Pembrokeshire Coast National Park. The Park oc ...

in the west through Carmarthenshire into Powys and

Monmouthshire Monmouthshire ( cy, Sir Fynwy) is a county in the south-east of Wales. The name derives from the historic county of the same name; the modern county covers the eastern three-fifths of the historic county. The largest town is Abergavenny, wit ...

and through the southern Welsh Marches, notably into

Herefordshire Herefordshire () is a county in the West Midlands of England, governed by Herefordshire Council. It is bordered by Shropshire to the north, Worcestershire to the east, Gloucestershire to the south-east, and the Welsh counties of Monmouths ...

, Worcestershire and

Gloucestershire Gloucestershire ( abbreviated Glos) is a county in South West England. The county comprises part of the Cotswold Hills, part of the flat fertile valley of the River Severn and the entire Forest of Dean. The county town is the city of ...

. Outliers in

Somerset ( en, All The People of Somerset) , locator_map = , coordinates = , region = South West England , established_date = Ancient , established_by = , preceded_by = , origin = , lord_lieutenant_office =Lord Lieutenant of Somerset , lor ...

and north

complete the extent of this basin. With the exception of south Pembrokeshire, all parts of the basin are represented by a range of lithologies assigned to the Lower Devonian and to the Upper Devonian, the contact between the two being unconformable and representing the complete omission of any Middle Devonian sequence. The lowermost formations are of upper Silurian age, these being the Downton Castle Sandstone Formation and the overlying Raglan Mudstone Formation except in Pembrokeshire where a more complex series of formations is recognised. In the east of the basin, the top of the Raglan Mudstone is marked by a well-developed

calcrete Caliche () is a sedimentary rock, a hardened natural cement of calcium carbonate that binds other materials—such as gravel, sand, clay, and silt. It occurs worldwide, in aridisol and mollisol soil orders—generally in arid or semiarid regions ...

, the Bishop's Frome Limestone. The lowermost Devonian formation is the St Maughans Formation, itself overlain by the Brownstones Formation though with an intervening Senni Formation over much of the area. The Upper Devonian sequence is rather thinner and comprises a series of formations which are more laterally restricted. In the

Brecon Beacons The Brecon Beacons ( cy, Bannau Brycheiniog, ) are a mountain range in South Wales. In a narrow sense, the name refers to the range of Old Red Sandstone peaks which lie to the south of Brecon. Sometimes referred to as "the central Beacons" ...

, the Plateau Beds Formation is unconformably overlain by the Grey Grits Formation though further east these divisions are replaced by the Quartz Conglomerate Group which is itself subdivided into a variety of different formations. Yensaby castle 1

Pembrokeshire

The sequence in Pembrokeshire differs from that of the main part of the basin and falls into two parts. In North Pembrokeshire to the north of the Ritec Fault, both the middle and upper ORS are missing with only the lower ORS present; this is divided into an earlier Milford Haven Group comprising in ascending order, the Red Cliff, Sandy Haven and Gelliswick Bay formations and a later Cosheston Group with, again in ascending order, its constituent Llanstadwell, Burton Cliff, Mill Bay, Lawrenny Cliff and New Shipping formations. These respectively equate with the Temeside, Raglan Mudstone and St Maughans formations of the central and eastern part of the basin. *''- middle and upper ORS missing -'' * Cosheston Group ** New Shipping Formation ** Lawrenny Cliff Formation ** Mill Bay Formation ** Burton Cliff Formation ** Llanstadwell Formation * Milford Haven Group ** Gelliswick Bay Formation ** Sandy Haven Formation (inc. Townsend Tuff Beds) ** Albion Sands Formation / Lindsway Bay Formation ** Red Cliff Formation In south Pembrokeshire to the south of the Ritec Fault, the lower ORS is represented by, in ascending order, the Freshwater East, Moors Cliff and Freshwater West formations. These are

unconformably An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval ...

overlain by the Ridgeway Conglomerate Formation. The middle ORS is missing whilst the Upper ORS is represented by the Gupton and West Angle formations. * Skrinkle Sandstone Group ** West Angle Formation ** Gupton Formation * ''- part of middle ORS missing -'' * Ridgeway Conglomerate Formation * ''- part of middle ORS missing -'' * Milford Haven Group ** Freshwater West Formation (inc. Rat Island Mudstone Member and Conigar Pit Sandstone Member) ** Moor Cliffs Formation (inc. Chapel point calcretes member and Townsend Tuff Bed) ** Freshwater East Formation The Freshwater East Formation, and corresponding Red Cliff Formation of north Pembrokeshire, are both late Silurian in age.

Anglesey

A small and separate basin exists here where both

and lacustrine deposits are recorded. Both the middle and upper ORS are missing but the lower ORS is represented, in ascending order, by the Bodafon, Traeth Bach, Porth y Mor and Traeth Lligwy formations.

Calcrete Caliche () is a sedimentary rock, a hardened natural cement of calcium carbonate that binds other materials—such as gravel, sand, clay, and silt. It occurs worldwide, in aridisol and mollisol soil orders—generally in arid or semiarid regions ...

s are also recorded representing carbonate-rich soils developed between periods of sediment deposition. The present day outcrop occupies a narrow zone from

Dulas Bay Dulas Bay ( Welsh: ''Bae Dulas'') is a small bay on the north east coast of Anglesey (''Ynys Môn''), north Wales, forming the boundary between Llaneilian and Moelfre communities. The bay is bordered by three beaches. Overview The north-wester ...

on Anglesey's northeast coast, southwards to the town of Llangefni.

History of study

In 1787

James Hutton James Hutton (; 3 June O.S.172614 June 1726 New Style. – 26 March 1797) was a Scottish geologist, agriculturalist, chemical manufacturer, naturalist and physician. Often referred to as the father of modern geology, he played a key role ...

noted what is now known as Hutton's Unconformity at Inchbonny,

Jedburgh Jedburgh (; gd, Deadard; sco, Jeddart or ) is a town and former royal burgh in the Scottish Borders and the traditional county town of the historic county of Roxburghshire, the name of which was randomly chosen for Operation Jedburgh in ...

, and in early 1788 he set off with John Playfair to the

coast and found more examples of this sequence in the valleys of the Tower and Pease Burns near

Cockburnspath Cockburnspath ( ; sco, Co’path) is a village in the Scottish Borders area of Scotland. It lies near the North Sea coast between Berwick-upon-Tweed and Edinburgh. It is at the eastern extremity of the Southern Upland Way a long-distance footp ...

. They then took a boat trip from Dunglass Burn east along the coast with the geologist

Sir James Hall Sir James Hall of Dunglass, 4th Baronet FRS FRSE (17 January 1761 – 23 June 1832) was a Scottish geologist and geophysicist. He was a Member of Parliament for St. Michael's borough (Mitchell, Cornwall) 1807–1812. Education Hall was born at Du ...

of Dunglass and at Siccar Point found what Hutton called "a beautiful picture of this junction washed bare by the sea", where 345-million-year-old Old Red Sandstone overlies 425-million-year-old

greywacke. In the early 19th century, the paleontology of the formation was studied intensively by

Hugh Miller Hugh Miller (10 October 1802 – 23/24 December 1856) was a self-taught Scottish geologist and writer, folklorist and an evangelical Christian. Life and work Miller was born in Cromarty, the first of three children of Harriet Wright (''b ...

Henry Thomas De la Beche Sir Henry Thomas De la Beche KCB, FRS (10 February 179613 April 1855) was an English geologist and palaeontologist, the first director of the Geological Survey of Great Britain, who helped pioneer early geological survey methods. He was the f ...

Roderick Murchison Sir Roderick Impey Murchison, 1st Baronet, (19 February 1792 – 22 October 1871) was a Scottish geologist who served as director-general of the British Geological Survey from 1855 until his death in 1871. He is noted for investigating and ...

, and

Adam Sedgwick Adam Sedgwick (; 22 March 1785 – 27 January 1873) was a British geologist and Anglican priest, one of the founders of modern geology. He proposed the Cambrian and Devonian period of the geological timescale. Based on work which he did on ...

—Sedgwick's interpretation was the one that placed it in the

: he coined the name of that period. The term 'Old Red Sandstone' was originally used in 1821 by Scottish naturalist and mineralogist Robert Jameson to refer to the red rocks which underlay the 'Mountain Limestone' i.e. the Carboniferous Limestone. They were thought at that time to be the British version of Germany's Rotliegendes, which is in fact of

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleo ...

age. Many of the

science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence ...

stratigraphy Stratigraphy is a branch of geology concerned with the study of rock layers ( strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithost ...

's early debates were about the Old Red Sandstone. In older geological works predating theories of

plate tectonics Plate tectonics (from the la, label= Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of larg ...

, the United States'

Catskill Delta The Devonian Catskill Formation or the Catskill Clastic wedge is a unit of mostly terrestrial sedimentary rock found in Pennsylvania and New York. Minor marine layers exist in this thick rock unit (up to ). It is equivalent to the Hampshire Form ...

formation is sometimes referred to as part of the Old Red Sandstone. In the modern day it is recognized that the two are not stratigraphically continuous but are very similar due to being formed at approximately the same time by the same processes.

Use as a building stone

The Old Red Sandstone has been widely used as a building stone across those regions where it outcrops. Notable examples of its use can be found in the area surrounding Stirling, Stonehaven,

Perth Perth is the capital and largest city of the Australian state of Western Australia. It is the fourth most populous city in Australia and Oceania, with a population of 2.1 million (80% of the state) living in Greater Perth in 2020. Perth is ...

and Tayside. The inhabitants of

Caithness Caithness ( gd, Gallaibh ; sco, Caitnes; non, Katanes) is a historic county, registration county and lieutenancy area of Scotland. Caithness has a land boundary with the historic county of Sutherland to the west and is otherwise bounded ...

at the northeastern tip of Scotland also used the stone to a considerable extent. Old Red Sandstone has also frequently been used in buildings in

and the former

Brecknockshire , image_flag= , HQ= Brecon , Government= Brecknockshire County Council (1889-1974) , Origin= Brycheiniog , Status= , Start= 1535 , End= ...

(now south Powys) of south Wales.

Notable buildings

;Canada * New York Life Insurance Building, Montreal ;England * Goodrich Castle,

Ross-on-Wye Ross-on-Wye (Welsh: ''Rhosan ar Wy'') is a market town in England, near the border with Wales. It had a population of 10,582 according to the 2011 census, estimated at 11,309 in 2019. It lies in south-eastern Herefordshire, on the River Wye a ...

market hall,

* Shrewsbury Castle,

Shropshire Shropshire (; alternatively Salop; abbreviated in print only as Shrops; demonym Salopian ) is a landlocked historic county in the West Midlands region of England. It is bordered by Wales to the west and the English counties of Cheshire to ...

* Hereford Cathedral,

;Scotland * Arbroath Abbey, Angus *

Muchalls Castle Muchalls Castle stands overlooking the North Sea in the countryside of Kincardine and Mearns, Aberdeenshire, Scotland. The lower course is a well-preserved Romanesque, double-groined 13th-century tower house structure, built by the Frasers o ...

, Aberdeenshire * St Magnus Cathedral, Orkney * Stonehaven Tolbooth, Aberdeenshire ;Wales *

Raglan Castle Raglan Castle ( cy, Castell Rhaglan) is a late medieval castle located just north of the village of Raglan in the county of Monmouthshire in south east Wales. The modern castle dates from between the 15th and early 17th centuries, when the succ ...

* Tintern Abbey,

http://www.museumwales.ac.uk/media/4/9/5/2/Newsletter_5.pdf *

Brecon Cathedral Brecon Cathedral ( cy, Eglwys Gadeiriol Aberhonddu), in the town of Brecon, Powys, is the cathedral of the Diocese of Swansea and Brecon in the Church in Wales and seat of the Bishop of Swansea and Brecon. Previously the church of Brecon Priory ...

, Powys

References

External links

{{commons category, Old Red Sandstone
Cawdor Castle — built from Old Red Sandstone
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