Lincoln Square is located on the site of San Juan Hill, a predominantly African American neighborhood of tenements. San Juan Hill was generally bordered by Amsterdam Avenue to the east, West End Avenue to the west, 59th Street to the south, and 65th Street to the north. It has been suggested that the area was named after the 10th Cavalry that fought with Theodore Roosevelt at the Battle of San Juan Hill during the Spanish–American War, but this is not certain. It was possibly the most heavily populated African-American neighborhood in Manhattan in the early 20th century. One of the blocks within the neighborhood contained almost 5,000 residents.