Lake Elkhorn is a 37 acre reservoir located in the Owen Brown area of Columbia, Maryland. It is Columbia's third and largest lake. Its main features are a small dam and a park with a picnic pavilion and a two-mile (3 km) walking path around the lake. The path was built in 1982. It is surrounded by a park and townhouses. The lake, which was built in 1974, is named for the Elkhorn branch of the Little Patuxent River