IATA Airport Code: SFO
Population: 4.594 million (2014 Metro)
Travelling around San Francisco
If staying in near the wharf district you will find that most sites can be seen in 1-2 days and accessed simply by walking. The trams are great to get to some of the shopping locations and are an attraction of themselves.
The key like many destinations is planning, learning what times the ferry is open for Alcatraz for example and then timing other sights all to fit into your schedule. To get the most out of travel the best start to your planning is to visit the sites that are only available in that city.