The Marine Mammal Centre in San Francisco

The Marine Mammal Centre is a nonprofit organisation that for decades has rescued and rehabilitated marine mammals such as whales, seals, porpoises, dolphins, manatees, dugongs, walruses, and others. It's located in the Marin Headlands north of the Golden Gate Bridge in Sausalito and offers tours and education. 

Here you can watch the rehabilitation process with the goal of releasing these wonderful, majestic creatures back into the wild, and you can learn about conservation and reclamation as well as the individual species housed here. Then you can head to the Golden Gate National Recreation Area for the opportunity to see them in their natural habitat.