I'm not sure which is but American Falls lies on the US's side and is separated by Goat Island.
Horshoe Falls is the largest and, funny enough, lies on the US border seperated by Goat Island (from Canada)
I would love to visit Niagara Falls. Oh really? That's the name for the 3 waterfalls between the Canada and US international border. Do each of the three also have individual names? They do. They are Horseshoe Falls, American Falls, and Bridal Veil Falls Which is the largest?
The Horseshoe Falls lies on the border of the United States and Canada with the American Falls entirely on the United States' side, separated by Goat Island.