Cohoes in Albany County, New York — The American Northeast (Mid-Atlantic)
Deep Gorge - Big Waterfall
Enormous quantities of water released from melting glaciers carved this gorge in less than 500 years. Almost all of New York had been covered by a mile-thick layer of ice. As the climate warmed and the ice front retreated, large pools of meltwater collected in lowland areas. Thirteen thousand years ago Glacial Lake Iroquois covered the basin now occupied by Lake Ontario, and the only path for water to drain from the Great Lakes to the sea was through the Mohawk Valley. The glacial Iro-Mohawk River carried over 100 times the flow of today's river- a torrent that quickly wore through soft shale, forming the deep gorge in front of you.
Shifting drainage patterns
Flows through the Mohawk Valley dropped dramatically once the ice retreated north of the Adirondack Mountains, allowing Lake Iroquois and the upper Great Lakes to drain through the Champlain and Hudson Valleys and later through the St. Lawrence Valley.
Mohawk Gorge below Cohoes Falls
The early Iro-Mohawk covered a wide area, and the river's surface would have been several feet above your head. Meltwater soon eroded a slot in the rock that captured all of the flow. Today's wildest floods fill only a small portion of the gorge carved by the Mohawk River's mighty ice-age predecessor.
Topics. This historical marker is listed in this topic list: Natural Features.
Location. 42° 47.152′ N, 73° 42.58′ W. Marker is in Cohoes, New York, in Albany County. It can be reached from North Mohawk Street. Marker is approximately 0.1 mile from the park entrance on Mohawk Street. Touch for map. Marker is in this post office area: Cohoes NY 12047, United States of America. Touch for directions.
Regionally, this marker is in Upstate New York, in the Capital District, and in the Albany Metropolitan Area. It is also in the American Northeast and in the Mid-Atlantic. Globally, it is in the North Atlantic Region, North America, the Western Hemisphere, the Western World, and the Anglosphere. Historically, it finds itself in what was once New Netherland and also one of the original Thirteen Colonies.
Other nearby markers. At least 8 other markers are within walking distance of this marker: Sightseeing / Cataract House, Cohoes Falls, N.Y. (here, next to this marker); Haudenosaunee Confederacy (within shouting distance of this marker); Navigating Around Cohoes Falls (about 300 feet away, measured in a direct line); Cohoes Falls / Lifeblood of Cohoes / Erie Canalway National Heritage Corridor (about 400 feet away); Canals, Water Power and Industry (about 400 feet away); How a Lock Works (about 500 feet away); Fourth Ward, First District (about 700 feet away); Honor Roll (about 700 feet away). Touch for a list and map of all markers in Cohoes.
Also see . . . Mohawk River (Wikipedia). (Submitted on August 6, 2025, by Steve Stoessel of Niskayuna, New York.)
Credits. This page was last revised on August 6, 2025. It was originally submitted on August 6, 2025, by Steve Stoessel of Niskayuna, New York. This page has been viewed 206 times since then and 33 times this year. Photos: 1, 2. submitted on August 6, 2025, by Steve Stoessel of Niskayuna, New York.

