What was the primary mode of transportation across the San Francisco bay prior to the Golden Gate Bridge?

The only (practical) way to get across the San Francisco Bay prior to 1937 was by Ferry. The Golden Gate Ferry Company, which became the largest ferry operation by the late 1920's, was established in 1867 as the Sausalito Land & Ferry Company. The ferry would take approximately 20 minutes and cost $1.00 per vehicle.