Tanforan Racetrack, also known as Tanforan Park, was a thoroughbred horse racing facility in San Bruno, on the San Francisco Peninsula, in California. It was in operation from November 4, 1899, to 1964. The horse racing track and buildings were constructed to serve a clientele from nearby San Francisco. Between April and October 1942, the racetrack was the site of the Tanforan Assembly Center, an internment camp in which 8,000 Bay Area Japanese Americans were detained and processed for forced relocation and internment.