The Peace Arch is a monument situated on the Canada–United States border between the communities of Blaine, Washington and Surrey, British Columbia. The Peace Arch, which stands 20.5 metres (67 ft) tall, was built by Sam Hill and dedicated in September 1921, and commemorates the signing of the Treaty of Ghent in 1814. The monument is built on the exact United States–Canada boundary, between Interstate 5 and Highway 99, in the grass median between the northbound and southbound lanes. The Peace Arch has the flags of the U.S. and Canada mounted on its crown, and two inscriptions on both sides of its frieze. The inscription on the U.S. side of the Peace Arch reads "Children of a common mother", and the words on the Canadian side read "Brethren dwelling together in unity".