Trimountain or Tri-mountain, est. , is a traprock mountain located southeast of

Meriden, Connecticut Meriden ( ) is a city in New Haven County, Connecticut, United States, located halfway between the regional cities of New Haven, Connecticut, New Haven and Hartford, Connecticut, Hartford. The city is part of the South Central Connecticut Planni ...

. It 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, Connecticut 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 United States census, 2020 U.S. census, New Haven is List ...

, north through the Connecticut River Valley of

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. Trimountain is known for its scenic cliff faces, unique

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 ...

ecosystems, and rare plant communities. The mountain is traversed by the Mattabesett Trail.

Geography

Trimountain is located in Durham and

Wallingford, Connecticut Wallingford is a town in New Haven County, Connecticut, New Haven County, Connecticut, United States, centrally located between New Haven, Connecticut, New Haven and Hartford, Connecticut, Hartford, and Boston and New York City. The town is part ...

. It takes its name from its overall triangular shape, its three southern pinnacles, and the three notches between the pinnacles. A prominent landscape feature that rises above the surrounding valleys, Trimountain is roughly long by wide, although the steepness of the terrain makes the actual square mileage much larger. Although Trimountain has been subject to intensive

quarrying A quarry is a type of open-pit mine in which dimension stone, rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some jurisdictions to manage their s ...

, which has obliterated much of the northwestern face of the mountain, the Mattabesett Trail still traverses the southern pinnacles and the wooded eastern side of the mountain. The Metacomet Ridge continues north from Trimountain as Besek Mountain and south as Fowler Mountain. The east side of Trimountain drains into the Coginchaug River, thence to the

Connecticut River 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 ...

and Long Island Sound; the west side drains into the Muddy River, thence 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 ...

and Long Island Sound.

Geology and ecology

Trimountain, like much of the Metacomet Ridge, is composed of

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 ...

, also called traprock, a

volcanic A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often fo ...

rock. The mountain formed near the end of the

Triassic Period 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 the ...

with 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 the

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 ...

n continent from

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 ...

and

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 ...

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 ...

welled up from the rift and solidified into sheets of strata hundreds of feet thick. Subsequent

faulting In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic ...

and

earthquake An earthquakealso called a quake, tremor, or tembloris the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they ...

activity tilted the strata, creating the cliffs and ridgeline of Trimountain. Hot, dry upper slopes, cool, moist ravines, and mineral-rich ledges of basalt talus produce a combination of

ecosystems on the mountain that support plant and animal species uncommon in greater Connecticut. Trimountain is also an important raptor migration path. (See

for more information on the geology and ecosystem of Trimountain).

Conservation and Recreation

Trimountain is used for

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 ...

, cross country skiing, and

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 ...

. The mountain is traversed by the Mattabesett Trail (maintained by the Connecticut Forest and Park Association), which stretches from the northern end of Lamentation Mountain, south to Totoket Mountain and north again to the Connecticut River. Trimountain State Park, and undeveloped property, is located on the southeastern side of the mountain. A trailhead for the Mattabesett Trail on Trimountain is located at the junction of Connecticut Route 68 and Connecticut Route 157 in Reeds Gap between Trimountain and Besek Mountain, west of Durham center. The ridgeline of Trimountain and its ecosystem is most threatened by quarrying and suburban development. The quarry on the western side of the mountain was approximately as of 2007. In 2000, Trimountain was included in a study by the

National Park Service The National Park Service (NPS) is an List of federal agencies in the United States, agency of the Federal government of the United States, United States federal government, within the US Department of the Interior. The service manages all List ...

for the designation of a new

National Scenic Trail The National Trails System is a series of trails in the United States designated "to promote the preservation of, public access to, travel within, and enjoyment and appreciation of the open-air, outdoor areas and historic resources of the Nati ...

now tentatively called the New England National Scenic Trail, which would include the Metacomet-Monadnock Trail in Massachusetts and the Mattabesett Trail and Metacomet Trail trails in Connecticut. The Wallingford Land Trust and the Middlesex Land Trust have been active in conserving the viewshed of Trimountain.

References

* Farnsworth, Elizabeth J.
Metacomet-Mattabesett Trail Natural Resource Assessment.
2004. PDF wefile cited November 1, 2007. * ''Connecticut Walk Book: A Trail Guide to the Connecticut Outdoors.'' 17th Edition. The Connecticut Forest and Park Association. Rockfall, Connecticut. Undated. * Raymo, Chet and Raymo, Maureen E. ''Written in Stone: A Geologic History of the Northeastern United States''. Globe Pequot, Chester, Connecticut, 1989.
U.S. Congress ''New England National Scenic Trail Designation Act.''

External links

Connecticut Forest and Park Association

U.S. Congress ''New England National Scenic Trail Designation Act.''

NPS brochure for National Scenic Trail proposal.

{{Mountains of Connecticut Mountains of Connecticut Wallingford, Connecticut Durham, Connecticut Metacomet Ridge Landforms of Middlesex County, Connecticut

Geography

Geology and ecology

Conservation and Recreation

See also

References

External links