Fort Point Channel is a maritime channel separating South Boston from downtown Boston, Massachusetts, feeding into Boston Harbor. The south part of it has been gradually filled in for use by the South Bay rail yard and several highways (specifically the Central Artery and the Southeast Expressway). At its south end, the channel once widened into South Bay, from which the Roxbury Canal continued southwest where the Massachusetts Avenue Connector is now. The Boston Tea Party occurred at its northern end.