 Before the late 20th century, the northeastern end of the Horseshoe Falls was in the United States, flowing around the Terrapin Rocks, which were once connected to Goat Island by a series of bridges.In 1955, the area between the rocks and Goat Island was filled in, creating Terrapin Point.In the early 1980s, the U.S. Army Corps of Engineers filled in more land and built diversion dams and retaining walls to force the water away from Terrapin Point.