Discover the revolutionary generation of Bostonians who blazed a trail from colonialism to independence. Boston National Historical Park is an association of sites that together give the visitor a coherent view of the city's role in the nation's history. In downtown Boston, Old South Meeting House, Old State House, Faneuil Hall, the Paul Revere House and Old North Church bring to life the American ideals of freedom of speech, religion, government, and self-determination. In Charlestown, visit the Bunker Hill Monument, the site of the first major battle of the American Revolution, the Charlestown Navy Yard, one of the nation's first naval shipyards and the USS Constitution, the oldest commissioned warship afloat in the world. Seven of the eight privately, municipally and federally owned and managed historic sites that comprise Boston National Historical Park are connected by the Freedom Trail, a 2.5-mile (4km) walking tour of 16 sites and structures of historic importance in downtown Boston and Charlestown. Located in South Boston and separate from the Freedom Trail, Dorchester Heights is significant for its role in the evacuation of the British from Boston during the Revolutionary War.