This map of Lake Ontario shows the valley of the Mohawk River, through which Glacial Lake Algonquin crossed the mountains to the Hudson River Valley. Lake Ontario is one of the five Great Lakes of North America. The Mohawk River is a long River in the US state of New York. Lake Algonquin was a Proglacial lake that existed in east-central North America at the time of the last Ice age. The Hudson River, called Muh-he-kun-ne-tuk, the Great Mohegan by the Iroquois, or as the Lenape Native Americans called it in Unami

Stages of great lake development.

Glacial Lake Iroquois was a prehistoric proglacial lake that existed at the end of the last ice age approximately 13,000 years ago. In Geology, a proglacial lake is a lake formed either by the Damming action of a Moraine or Ice dam during the retreat of a melting glacier or An ice age is a period of long-term reduction in the Temperature of the Earth 's surface and atmosphere resulting in an expansion of continental Ice sheets The lake was essentially an enlargement of the present Lake Ontario that formed because the St. Lawrence River downstream from the lake was blocked by the ice sheet near the present Thousand Islands. Lake Ontario is one of the five Great Lakes of North America. Saint Lawrence River (in French: fleuve Saint-Laurent; Kahnawáˀkye in Tuscarora, Kaniatarowanenneh meaning big waterway The Thousand Islands is the name of an archipelago of Islands that straddle the U The level of the lake was approximately 30 m (~100 ft) above the present level of Lake Ontario.

The lake drained to the southeast, through a channel passing near present day Rome, New York. Rome is a City in Oneida County, New York, United States. The population was 34950 at the 2000 census. The channel then followed the valley of the Mohawk River to the Hudson River. The Mohawk River is a long River in the US state of New York. The Hudson River, called Muh-he-kun-ne-tuk, the Great Mohegan by the Iroquois, or as the Lenape Native Americans called it in Unami

The lake was fed by Early Lake Erie, as well as Glacial Lake Algonquin, an early partial manifestation of Lake Huron, that drained directly to Lake Iroquois across southern Ontario, along the southern edge of the ice sheet, bypassing Early Lake Erie. Early Lake Erie was a prehistoric Proglacial lake that existed at the end of the last Ice age approximately 13000 years ago Lake Algonquin was a Proglacial lake that existed in east-central North America at the time of the last Ice age. Lake Huron, bounded on the west by the US state of Michigan, and on the east by the province of Ontario, Canada, is one of the five Great Ontario (ɒnˈtɛrioʊ is a province located in the central part of Canada, the largest by population and second largest after Quebec

The subsequent melting of the ice dam resulted in a sudden lowering of the lake to its present level, and setting off the Younger Dryas episode. The Younger Dryas Stadial, named after the alpine / tundra wildflower Dryas octopetala, and also referred to as the Big Freeze, was a brief (approximately

The prehistoric shoreline, marked by a ridge known as the Iroquois Shoreline, can be discerned in places around Lake Ontario. Iroquois Shoreline was the shore of the Glacial Lake Iroquois, now part of the current Lake Ontario. This can be seen, for instance, in Toronto parallelling Davenport Road near Spadina Avenue, and also nearby in Scarborough, Ontario, where the prehistoric shoreline takes the form of earthen cliffs at the modern lakeshore (called the Scarborough Bluffs). Toronto (təˈrɒntoʊ colloquially pronounced or) is the largest city in Canada and is the provincial capital of Ontario Scarborough (ˈskɑrˌbəroʊ ( 2001 Census 593297 is the area that forms the eastern part of the City of Toronto, Ontario, Canada The Scarborough Bluffs are an Escarpment in Scarborough Ontario along the shoreline of Lake Ontario.

See also

• List of prehistoric lakes

External links

• History of Lake Iroquois
• Lake Iroquois and its shore cliff, showing map of the lake
• Deglaciation of the Central St. Lawrence Lowland