Washington Square, originally designated in 1682 as Southeast Square, is an open-space park in Center City Philadelphia's Southeast quadrant and one of the five original planned squares laid out on the city grid by William Penn. It is part of both the Washington Square West and Society Hill neighborhoods. The Tomb of the Unknown Soldier memorial is located within the square. The bodies of an unknown number of soldiers remain buried beneath the square and the surrounding area; some are still occasionally found during construction and maintenance projects.