city, southwestern British Columbia, Canada. It lies just southeast of Vancouver on the northern shore of Semiahmoo Bay, at the entrance to the Strait of Georgia. The city is named for a large white rock that, according to an Indian legend, was thrown across the water from Vancouver Island (to the west) by a sea god's son. The rock was used as a navigational aid by early mariners. White Rock is a Pacific port of entry directly northwest of Blaine, Wash., and part of the Vancouver metropolitan area. The site, laid out in 1905, soon became a vacation area. Peace Arch (1921) and International Park mark the western extremity of the U.S.-Canadian border. The city has a large retired-worker community. Pop. (2006) 18,755.