Fleet Week is officially upon us, and that means that in addition to the Blue Angels flying above, the Bay is going to be teeming with Navy vessels all week long. To kick things off, ABC 7 captured the cool time-lapse video embedded above showing the USS San Diego entering the Bay yesterday.

The video also depicts a Navy tradition of the ship's crew "manning the rails." Apparently it developed as a way, before radios existed, for a crew to demonstrate to a port they entered that they had no hostile intentions.

You can see more ships at 10:00 a.m. this Friday during the scheduled "Parade of Ships."

Previously: Fleet Week Starts Today: Complete Schedule, Where To Watch The Blue Angels, And A Reminder To Hide Your Pets