The San Francisco Zoo is a 100-acre zoo. Now that’s pretty darn big! It is located in the south west corner of San Francisco. It is easily accessible from the peninsula and from San Francisco proper.
If you have friends in the East Bay, we would rather suggest the Oakland Zoo in Oakland CA.
The San Francisco Zoo is known for it’s wonderful monkey exhibit, the insect exhibit, and a tiger grotto which has been updated in recent years for an even better visitor experience.