San Francisco Bar Pilots Association is the official maritime pilot group for the San Francisco harbor and associated waterways.
[2] The association is the oldest purely maritime organization on the Pacific coast of the United States predating the oldest lighthouse in California erected on Alcatraz Island in 1854.
[3] The "bar" referred to in their name is a large sandbar in the Pacific Ocean just outside of the Golden Gate which poses a significant hazard to arriving ships.
[3] In 1910 the 58 feet 2 inches (17.7 m) motor boat California was built for the pilots.
[4] In 1935 three schooner pilot vessels were maintained to provide rotating five-day watches on the bar near the lightship with two, the large schooner California and Gracie S. being regulars with Adventuress as reserve.