East Rock of south-central

Connecticut Connecticut ( ) is a U.S. state, state in the New England region of the Northeastern United States. It borders Rhode Island to the east, Massachusetts to the north, New York (state), New York to the west, and Long Island Sound to the south. ...

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

, 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 of the U.S. state of Connecticut. It is located on New Haven Harbor on the northern shore of Long Island Sound. With a population of 135,081 as determined by the 2020 U.S. census, New Haven is the third largest city in Co ...

. 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 sound (geography), 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 (state), New York to the south. From west to east, ...

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 into Long Isl ...

Massachusetts Massachusetts ( ; ), officially the Commonwealth of Massachusetts, is a U.S. state, state in the New England region of the Northeastern United States. It borders the Atlantic Ocean and the Gulf of Maine to its east, Connecticut and Rhode ...

to the

Vermont Vermont () is a U.S. state, state in the New England region of the Northeastern United States. It borders Massachusetts to the south, New Hampshire to the east, New York (state), New York to the west, and the Provinces and territories of Ca ...

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, 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 New England town, town in New Haven County, Connecticut, United States. The town's nickname is "The Land of the Sleeping Giant (Connecticut), Sleeping Giant". The town is part of the South Central Connecticut Planning Region, Connecti ...

, 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 in 1793, one of the key inventions of the Industrial Revolution that shaped the economy of the Antebellum South. Whitney's ...

, 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 (); ...

and a former New Haven resident. The Eli Whitney Museum, 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 the armed conflict that comprised the final eight years of the broader American Revolution, in which Am ...

, the

War of 1812 The War of 1812 was fought by the United States and its allies against the United Kingdom of Great Britain and Ireland, United Kingdom and its allies in North America. It began when the United States United States declaration of war on the Uni ...

, the Mexican War, and the

Civil War A civil war is a war between organized groups within the same Sovereign state, 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 policies.J ...

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

East Rock is located entirely within the 425-acre (172 ha) East Rock Park, 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 Revivalism (architecture), 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 st ...

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

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 is the primary north–south thoroughfare in the western part of the region. Its southern terminus is in New Haven, Connecticut, at I-95, whi ...

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; it extends east over another series of traprock outcrops to Saltonstall Mountain and Peter's Rock. 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 ...

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

Geology

East Rock is a fault-block ridge formed 200 million years ago during the

Triassic The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...

and

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

periods and is composed of

, known as

basalt Basalt (; ) is an aphanite, 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 planetary surface, surface of a terrestrial ...

, 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 contr ...

, 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-gra ...

, 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. The term ''scree'' is ap ...

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 Natural satellite, moon onto its surface. Lava may be erupted at a volcano or through a Fissure vent, fractu ...

intrusions hundreds of feet deep that welled up through faults creating sills 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 Fault (geology), downfaulted depression, called a graben, or more commonly ...

apart of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

from

Eurasia Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, Physical geography, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents d ...

and

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

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 atmosphere of Earth, atmospheric conditions that differ from those in the surrounding areas, often slightly but sometimes substantially. The term may refer to areas as small as a few square m ...

s unusual in

New England New England is a region consisting of 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 (state), New York to the west and by the ...

. 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. It is also generally characterized by an understory that is lush with grass and herb-related plants. The terms "oakery" or ...

s, often dominated by chestnut oak and a variety of understory grasses and ferns.

Eastern red cedar ''Juniperus virginiana'', also known as eastern redcedar, 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 an ...

, 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 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 continental island in southeastern New York (state), New York state, extending into the Atlantic Ocean. It constitutes a significant share of the New York metropolitan area in both population and land are ...

. East Rock Park 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 A hike is a long, vigorous walk, usually on trails or footpaths in the countryside. Walking for pleasure developed in Europe during the eighteenth century. Long hikes as part of a religious pilgrimage have existed for a much longer time. "Hi ...

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 footw ...

cross-country skiing Cross-country skiing is a form of skiing whereby skiers traverse snow-covered terrain without use of ski lifts or other assistance. Cross-country skiing is widely practiced as a sport and recreational activity; however, some still use it as a m ...

, picnicking,

bicycling Cycling, also known as bicycling or biking, is the activity of riding a bicycle or other types of bicycle pedal, pedal-driven human-powered vehicles such as balance bikes, unicycles, tricycles, and quadricycles. Cycling is practised around the ...

(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 such as binoculars or a telescop ...

, and dog walking.

Rock climbing Rock climbing is a climbing sports discipline that involves ascending climbing routes, routes consisting of natural rock in an outdoor environment, or on artificial resin climbing walls in a mostly indoor environment. Routes are documented in c ...

swimming Swimming is the self-propulsion of a person through water, such as saltwater or freshwater environments, usually for recreation, sport, exercise, or survival. Swimmers achieve locomotion by coordinating limb and body movements to achieve hydrody ...

, and

alcoholic beverage Drinks containing alcohol (drug), alcohol are typically divided into three classes—beers, wines, and Distilled beverage, spirits—with alcohol content typically between 3% and 50%. Drinks with less than 0.5% are sometimes considered Non-al ...

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 Federal government of the United States, United States federal government's official United States National Register of Historic Places listings, list of sites, buildings, structures, Hist ...

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 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