Early in the 19th century, landfill was used to expand Lower Manhattan from the natural Hudson shoreline at Greenwich Street to West Street. When building the World Trade Center in 1968, 1.2 million cubic yards (917,000 m3) of material was excavated from the site. Rather than dumping the spoil at sea or in landfills, the fill material was used to expand the Manhattan shoreline across West Street, creating Battery Park City. The result was a 700-foot (210-m) extension into the river, running six blocks or , covering , providing a riverfront esplanade and over of parks; Hudson River Park was subsequently opened in stages beginning in 1998.