The floating pontoons of Pier 39 are the kingdom of sealions, whose barking fills the air and whom you will see playing, sleeping on top of one another or nonchalantly eyeing the onlookers. You must not feed them to avoid making them dependent on humans and less wary of fishermen and their boats! The rest of the pier is a bustling mall rich in attractions. The Aquarium of the Bay provides an insight into the region's maritime environments.