Sometimes called the Jewel of Oakland, Lake Merritt is the only city in the United States with a salt water lake in the downtown metropolitan area. Originally part of the San Francisco bay, in 1869, Oakland Mayor Dr. Samual Merritt donated money to build a dam at the 12th Street bridge, across the "neck" of the inlet, thus creating the present day lake. It was called "Merritt's Lake", and gradually over time became Lake Merritt.