Much of the Hudson Canyon was formed during the last Ice Age, over 10,000 years ago, when the sea level was about 400 feet lower and the mouth of the Hudson River was near the edge of the continental shelf, about 100 miles east of its present site.

http://news.yahoo.com/s/ap/20060904/ap_on_sc/sea_floor_mapping

Much of the Hudson Canyon was formed during the last Ice Age, over 10,000 years ago,


when the sea level was about 400 feet lower


and the mouth of the Hudson River was near the edge of the continental shelf,


about 100 miles east of its present site.


Scientists map canyon below Atlantic
.