Named after the last Aztec Emperor Cuauhtémoc who was captured and killed way back in 1525, the ARM Cuauhtémoc arrived in San Francisco today. Weighing a massive 1,800 tons and measuring 220 ft., the tall ship, which is used as a sail training vessel for the Mexican Navy, will be docked at Pier 27 and open for visitors through July 17. (Hours are 1 p..m - 5 p.m. for today, 10 a.m. - 10 p.m. for the rest of the week.)