In 1860–1861, Rio Vista was located 17 miles north of here, and Pony Express mail usually traveled both ways between San Francisco and Sacramento by steamboat slough on California Steam Navigation Company river steamers, which stopped at Benicia and Rio Vista. The first eastbound river steamer to carry Pony Express mail was either the “New World” or the “Antelope,” leaving San Francisco on April 3, 1860, at 4:00 p.m. with 56 Pony Express letters and arriving here around 10:30 p.m. The first westbound river steamer carrying Pony Express mail was the “Antelope,” which left Sacramento on April 13, 1860, at 5:45 p.m. and arrived at Rio Vista around 7:50 p.m. The last Pony Express mail was carried to San Francisco on November 20, 1861, by the river steamer “Chrysopolis.”