
It is based on the city of San Francisco, California, with the additional references of two Firth of Forth bridges in Scotland, the Forth Bridge and the Forth Road Bridge, the latter being made to also resemble the San Francisco-Oakland Bay Bridge in both design and physical location. San Fierro is the smallest city in area and the second largest in population in San Andreas, situated on a peninsula in the western portion of the state. There is also mention of an unnamed state capital.

For example, some maps found in the game connect San Andreas to a mainland. There are hints that more areas of San Andreas exist, but are simply not included for gameplay purposes.

The state is divided into three cities and five counties: the cities of Los Santos, San Fierro and Las Venturas and the counties of Red County, Flint County, Whetstone, Tierra Robada and Bone County. The in-game San Andreas is square-shaped and its area is estimated to be 33 square kilometres in size (12.7 square miles), the largest setting in the Grand Theft Auto series up until Grand Theft Auto V's rendition of part of the same state. San Andreas appears to be comprised entirely of islands, as the state is surrounded by water however, several maps throughout the state depict the northern regions ( Tierra Robada and Bone County) connecting to the mainland (despite this, it is possible to completely circumnavigate the state by boat).
