Georgetown was located at the juncture of the Alexandria Canal and the Chesapeake and Ohio Canal. The C&O Canal, begun in Georgetown in 1829, reached Cumberland, Maryland in 1851, and operated until 1924. Wisconsin Avenue is on the alignment of the tobacco hogshead rolling road from rural Maryland, and the Federal Customs House was located on 31st Street (now utilized as the post office). The city's oldest bridge, the sandstone bridge which carries Wisconsin Avenue over the C&O Canal, and which dates to 1831, was reopened to traffic on May 16, 2007, after a $3.5 million restoration. It is the only remaining bridge of five constructed in Georgetown by the Chesapeake & Ohio Canal Company.