Black Diamond city, Washington (data.census.gov)Black Diamond city, Washington is a city, town, place equivalent, or township located in Washington. Black Diamond city, Washington has a land area of 6.5 square miles.
Black Diamond, Washington (Wikipedia)Black Diamond is a city in King County, Washington, United States. The population was 4,697 at the 2020 census. In 2023, with a 40.6% growth rate, Black Diamond was the fastest growing small city in King County.
