East Rock of south-central

Connecticut Connecticut () is the southernmost state in the New England region of the Northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, New York (state), New York to the west, and Long Island Sound to the ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

, with a high point of , is a long

trap rock Trap rock, also known as either trapp or trap, is any dark-colored, fine-grained, non-granitic intrusive or extrusive igneous rock. Types of trap rock include basalt, peridotite, diabase, and gabbro.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. ...

ridge located primarily in the neighborhood of East Rock on the north side of the city of

New Haven New Haven is a city in the U.S. state of Connecticut. It is located on New Haven Harbor on the northern shore of Long Island Sound in New Haven County, Connecticut and is part of the New York City metropolitan area. With a population of 134,023 ...

. A prominent landscape feature and a popular outdoor recreation area with cliffs that rise over the city below, East Rock is part of the narrow, linear

Metacomet Ridge The Metacomet Ridge, Metacomet Ridge Mountains, or Metacomet Range of southern New England is a narrow and steep fault-block mountain ridge known for its extensive cliff faces, scenic vistas, microclimate ecosystems, and rare or endangered plants. ...

that extends from

Long Island Sound Long Island Sound is a marine sound and tidal estuary of the Atlantic Ocean. It lies predominantly between the U.S. state of Connecticut to the north and Long Island in New York to the south. From west to east, the sound stretches from the Eas ...

near New Haven, north through the

Connecticut River Valley The Connecticut River is the longest river in the New England region of the United States, flowing roughly southward for through four states. It rises 300 yards (270 m) south of the U.S. border with Quebec, Canada, and discharges at Long Island ...

Massachusetts Massachusetts (Massachusett: ''Muhsachuweesut Massachusett_writing_systems.html" ;"title="nowiki/> məhswatʃəwiːsət.html" ;"title="Massachusett writing systems">məhswatʃəwiːsət">Massachusett writing systems">məhswatʃəwiːsət'' En ...

to the

Vermont Vermont () is a U.S. state, state in the northeast New England region of the United States. Vermont is bordered by the states of Massachusetts to the south, New Hampshire to the east, and New York (state), New York to the west, and the Provin ...

border.Farnsworth, Elizabeth J
"Metacomet-Mattabesett Trail Natural Resource Assessment."
, 2004. PDF file. Cited Nov. 20, 2007.DeLorme Topo 6.0. Mapping Software. DeLorme, Yarmouth, Maine East Rock is the central feature of

East Rock Park East Rock Park is a park in the city of New Haven and the town of Hamden, Connecticut that is operated as a New Haven city park. The park surrounds and includes the mountainous ridge named East Rock and was developed with naturalistic landscaping ...

, a municipal park owned by the city of New Haven along the New Haven-Hamden town line.

Geography

East Rock, located in

and

Hamden, Connecticut Hamden is a town in New Haven County, Connecticut, United States. The town's nickname is "The Land of the Sleeping Giant". The population was 61,169 at the 2020 census. History The peaceful tribe of Quinnipiacs were the first residents of the ...

, is long by wide at its widest point, although steepness of the terrain make the actual land area much larger. Beside the high point, East Rock has three other distinct peaks: Whitney Peak, , a sharp-sided pinnacle on the north side of the ridge; Indian Head, , just south of the high point; and Snake Rock, , the southern buttress of the ridge. Whitney Peak and Lake Whitney (located at the western base of the mountain behind the dammed Mill River) are named after

Eli Whitney Eli Whitney Jr. (December 8, 1765January 8, 1825) was an American inventor, widely known for inventing the cotton gin, one of the key inventions of the Industrial Revolution that shaped the economy of the Antebellum South. Although Whitney hi ...

, the inventor of the

cotton gin A cotton gin—meaning "cotton engine"—is a machine that quickly and easily separates cotton fibers from their seeds, enabling much greater productivity than manual cotton separation.. Reprinted by McGraw-Hill, New York and London, 1926 (); a ...

and a former New Haven resident. The

Eli Whitney Museum The Eli Whitney Museum, in Hamden, Connecticut, is an experimental learning workshop for students, teachers, and families. The museum's main building is located on a portion of the Eli Whitney Gun Factory site, a gun factory erected by Eli Whit ...

, a museum and workshop with hands-on projects and exhibits on Eli Whitney and A. C. Gilbert, is located at the base of the dam. On the summit of East Rock, clearly visible for miles below, is the Soldiers and Sailors Monument. The monument honors the residents of New Haven who gave their lives in the

American Revolutionary War The American Revolutionary War (April 19, 1775 – September 3, 1783), also known as the Revolutionary War or American War of Independence, was a major war of the American Revolution. Widely considered as the war that secured the independence of t ...

, the

War of 1812 The War of 1812 (18 June 1812 – 17 February 1815) was fought by the United States of America and its indigenous allies against the United Kingdom and its allies in British North America, with limited participation by Spain in Florida. It be ...

, the Mexican War, and the

Civil War A civil war or intrastate war is a war between organized groups within the same state (or country). The aim of one side may be to take control of the country or a region, to achieve independence for a region, or to change government polici ...

.City of New Haven
cited Dec. 22, 2007. East rock winter

East Rock is located entirely within the 425-acre (172 ha)

, managed by the city of New Haven, which maintains a seasonal automobile road that climbs to the summit of the ridge, a network of trails, an environmental center, and a rose garden. A number of recreation facilities are located at the southwest base of the ridge; these are also managed by the city. The ridge is completely surrounded by the urban neighborhoods of New Haven and its metropolitan extension into south Hamden. East Rock lends its name to the nearby upscale East Rock neighborhood of New Haven, known for its Queen Anne and

Victorian architecture Victorian architecture is a series of architectural revival styles in the mid-to-late 19th century. ''Victorian'' refers to the reign of Queen Victoria (1837–1901), called the Victorian era, during which period the styles known as Victorian w ...

U.S. Route 5 U.S. Route 5 (US 5) is a north–south United States highway running through the New England states of Connecticut, Massachusetts, and Vermont. Significant cities along the route include New Haven, Connecticut; Hartford, Connecticut; and Springf ...

borders the east side of East Rock while

Interstate 91 Interstate 91 (I-91) is an Interstate Highway in the New England region of the United States. It provides the primary north–south thoroughfare in the western part of the region. The Interstate generally follows the course of the Connec ...

crosses below Snake Rock to the south. The Metacomet Ridge extends west from East Rock as series of smaller, unnoteworthy traprock outcrops to

West Rock Ridge West Rock Ridge or West Rock of south-central Connecticut, is a long trap rock mountain ridge located on the west side of New Haven with a high point of . The ridge forms a continuous line of exposed cliffs visible from metropolitan New Haven a ...

; it extends east over another series of traprock outcrops to Saltonstall Mountain and

Peter's Rock Peter's Rock, also known as Rabbit Rock, Rabbit Hill, Indian Rock and Great Rock, with a high point of (est.) above sea level, is a trap rock peak located northeast of downtown New Haven, Connecticut in the town of North Haven. It is part of ...

. The west side of East Rock drains into the Mill River thence to New Haven Harbor and Long Island Sound; the east side into the

Quinnipiac River The Quinnipiac River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed April 1, 2011 long river in the New England region of the United States, located entirely in the state of Conne ...

, thence to New Haven Harbor and Long Island Sound. Both rivers abut the base of the mountain.

Geology

East Rock is a

fault-block Fault blocks are very large blocks of rock, sometimes hundreds of kilometres in extent, created by tectonic and localized stresses in Earth's crust. Large areas of bedrock are broken up into blocks by faults. Blocks are characterized by relat ...

ridge formed 200 million years ago during the

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest per ...

and

Jurassic The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...

periods and is composed of

, known as

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 ...

, if

extrusive Extrusive rock refers to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out (extrudes) onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics or tuff. In contra ...

, or

diabase Diabase (), also called dolerite () or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grain ...

, if intrusive. East Rock, being intrusive, is diabase. Diabase is a dark colored rock, but the iron within it weathers to a rusty brown when exposed to the air, lending the ledges a distinct reddish appearance. Diabase frequently breaks into octagonal and pentagonal columns, creating a unique "postpile" appearance. Huge slopes made of fractured diabase

scree Scree is a collection of broken rock fragments at the base of a cliff or other steep rocky mass that has accumulated through periodic rockfall. Landforms associated with these materials are often called talus deposits. Talus deposits typically ...

are visible beneath many of the ledges of East Rock. These diabase cliffs are the product of

lava Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or ...

intrusions hundreds of feet deep that welled up through faults creating

sill Sill may refer to: * Sill (dock), a weir at the low water mark retaining water within a dock * Sill (geology), a subhorizontal sheet intrusion of molten or solidified magma * Sill (geostatistics) * Sill (river), a river in Austria * Sill plate, ...

s during the

rifting In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben wi ...

apart 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 ...

from

Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelag ...

and

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

over a period of 20 million years. Erosion and glacial abrasion over the subsequent 200 million years wore away the weaker sedimentary layers, under which the sill had intruded, at a faster rate than the diabase, leaving the abruptly tilted edges of the diabase sheets exposed, creating the distinct linear ridge and dramatic cliff faces visible today.

Ecosystem

East Rock hosts a combination of

microclimate A microclimate (or micro-climate) is a local set of atmospheric conditions that differ from those in the surrounding areas, often with a slight difference but sometimes with a substantial one. The term may refer to areas as small as a few squ ...

s unusual in

New England New England is a region comprising six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York to the west and by the Canadian provinces ...

. Dry, hot upper ridges support

oak savanna An oak savanna is a type of savanna—or lightly forested grassland—where oaks (''Quercus ''spp.) are the dominant trees. The terms "oakery" or "woodlands" are also used commonly, though the former is more prevalent when referencing the Medite ...

s, often dominated by

chestnut oak ''Quercus montana'', the chestnut oak, is a species of oak in the white oak group, ''Quercus'' sect. ''Quercus''. It is native to the eastern United States, where it is one of the most important ridgetop trees from southern Maine southwest ...

and a variety of understory grasses and ferns.

Eastern red cedar ''Juniperus virginiana'', also known as red cedar, eastern red cedar, Virginian juniper, eastern juniper, red juniper, and other local names, is a species of juniper native to eastern North America from southeastern Canada to the Gulf of Mexico a ...

, a dry-loving species, clings to the barren edges of cliffs. Cooler north facing backslopes tend to support extensive stands of

eastern hemlock ''Tsuga canadensis'', also known as eastern hemlock, eastern hemlock-spruce, or Canadian hemlock, and in the French-speaking regions of Canada as ''pruche du Canada'', is a coniferous tree native to eastern North America. It is the state tree of ...

interspersed with the oak-hickory forest species more common in the surrounding lowlands. Narrow ravines crowded with hemlock block sunlight, creating damp, cooler growing conditions with associated cooler climate plant species. Talus slopes are especially rich in nutrients and support a number of calcium-loving plants uncommon in eastern Connecticut.The Traprock Wilderness Recovery Strategy
. Cited Dec. 13, 2007 East Rock is also an important seasonal

raptor Raptor or RAPTOR may refer to: Animals The word "raptor" refers to several groups of bird-like dinosaurs which primarily capture and subdue/kill prey with their talons. * Raptor (bird) or bird of prey, a bird that primarily hunts and feeds on v ...

migration path.

Recreation

East Rock is a popular outdoor recreation destination among residents and visitors of the greater New Haven region. Views from the clifftops span metropolitan New Haven, Long Island Sound, and

Long Island Long Island is a densely populated island in the southeastern region of the U.S. state of New York, part of the New York metropolitan area. With over 8 million people, Long Island is the most populous island in the United States and the 18 ...

is open year-round to hikers and walkers. The automobile road is open April 1 to November 1, 8 a.m. to sunset and November 1 to March 31, Friday, Saturday, Sunday, and holidays, 8 a.m. to 4 p.m., weather permitting. Activities permitted in the park include

hiking Hiking is a long, vigorous walk, usually on trails or footpaths in the countryside. Walking for pleasure developed in Europe during the eighteenth century.AMATO, JOSEPH A. "Mind over Foot: Romantic Walking and Rambling." In ''On Foot: A Histor ...

snowshoeing Snowshoes are specialized outdoor gear for walking over snow. Their large footprint spreads the user's weight out and allows them to travel largely on top of rather than through snow. Adjustable bindings attach them to appropriate winter footwe ...

cross-country skiing Cross-country skiing is a form of skiing where skiers rely on their own locomotion to move across snow-covered terrain, rather than using ski lifts or other forms of assistance. Cross-country skiing is widely practiced as a sport and recreatio ...

picnicking A picnic is a meal taken outdoors ( ''al fresco'') as part of an excursion, especially in scenic surroundings, such as a park, lakeside, or other place affording an interesting view, or else in conjunction with a public event such as preceding ...

bicycling Cycling, also, when on a two-wheeled bicycle, called bicycling or biking, is the use of cycles for transport, recreation, exercise or sport. People engaged in cycling are referred to as "cyclists", "bicyclists", or "bikers". Apart from two ...

(on roads and city-designated mountain bike trails only),

boating Boating is the leisurely activity of travelling by boat, or the recreational use of a boat whether powerboats, sailboats, or man-powered vessels (such as rowing and paddle boats), focused on the travel itself, as well as sports activities, suc ...

(on the Mill River),

bird watching Birdwatching, or birding, is the observing of birds, either as a recreational activity or as a form of citizen science. A birdwatcher may observe by using their naked eye, by using a visual enhancement device like binoculars or a telescope, by ...

, and

dog walking Dog walking is the act of a person walking with a dog, typically from the dog's residence and then returning. Leashes are commonly used for this. Both owners and pets receive many benefits, including exercise and companionship. Description ...

Rock climbing Rock climbing is a sport in which participants climb up, across, or down natural rock formations. The goal is to reach the summit of a formation or the endpoint of a usually pre-defined route without falling. Rock climbing is a physically a ...

swimming Swimming is the self-propulsion of a person through water, or other liquid, usually for recreation, sport, exercise, or survival. Locomotion is achieved through coordinated movement of the limbs and the body to achieve hydrodynamic thrust that r ...

, and

alcoholic beverage An alcoholic beverage (also called an alcoholic drink, adult beverage, or a drink) is a drink that contains ethanol, a type of Alcohol (chemistry), alcohol that acts Alcohol (drug), as a drug and is produced by Ethanol fermentation, fermentat ...

s are prohibited. A number of hiking trails traverse the ridge, most notably the Giant Steps Trail which ascends to the summit at a near-vertical pitch from the south. At the foot of the mountain are located football, baseball, and soccer fields, tennis courts, basketball courts, and playgrounds. The Trowbridge Environmental Center is open Thursdays and Fridays from 10:00 am to 5:00 pm, and at least one Saturday a month for public programs; it offers displays and information about the geology and ecosystem of East Rock. The Pardee Rose Garden and Greenhouse features roses and other flowering plants from spring to fall, and is a popular place to shoot wedding pictures. The naturalist landscaping and other aspects of the park led to its being listed on the

National Register of Historic Places The National Register of Historic Places (NRHP) is the United States federal government's official list of districts, sites, buildings, structures and objects deemed worthy of preservation for their historical significance or "great artistic ...

in 1997.

References

External links

City of New Haven map of East Rock Park

City of New Haven East Rock Park page

City of New Haven

West Rock State Park

East Rock Park in & out
* New Haven Mayor's Office
A Brief History of the Angel of Peace and the New Haven Soldiers’ and Sailors’ Monumentthe Four Rocks of the New Haven James Dwight Dana 1891
{{Mountains of Connecticut Hamden, Connecticut Metacomet Ridge, Connecticut Landforms of New Haven County, Connecticut Mountains of Connecticut Tourist attractions in New Haven County, Connecticut Geography of New Haven, Connecticut Tourist attractions in New Haven, Connecticut