Having San Francisco revealed on your map can only happen right before you get there, oddly enough. In the The Military Base, you will find a Survey Map held in a footlocker in one of the outter tents that will reveal San Francisco's location after using it. Geographically, this is very close to San Francisco, so having it revealed at this stage isn't terribly useful.
If you want to know which cities to visit, I would suggest that NCR (New California Republic) should be the last city that you visit before trekking out to San Francisco.
To clear up any confusion, there are a few NPC's which will mention San Francisco beforehand, however they will not reveal it on the map:
- Doc Holliday in Broken Hills tells you a story about San Francisco. You can relay this story to the doctor in San Francisco, but this will not reveal San Francisco's location.
- Brotherhood of Steel's NCR outpost will tell you to visit their San Francisco outpost if you pass a level check, however this will not reveal San Francisco's location.
- The Hubologist in NCR will give you a letter to deliver to San Francisco if you manage to pass a speech check, but this also will not reveal San Francisco on your map.
SPOILERS / DIRECTIONS BELOW: (mouse over to reveal)
If you are following the general path that the game is intended to be played out in (see link for map), you will likely come upon New Reno or Broken Hills. Moving on from there, you will likely travel South to NCR. From NCR, you travel West until you hit The Military Base, and then San Francisco.
Alternatively, you could simply leave from Arroyo (where you start the game) and head straight South to San Francisco, saving often to avoid being killed by random encounters.
- If you are going to play through Fallout 2, I highly recommend installing the Fallout 2 Resoration Project 2.1.2b. It fixes many problems with the game (including technical problems on modern systems) as well as adding additional content should you desire it.
- Refer to this guide if you need any help. Use the search function to find keywords. Everything in the game is in there.
- If you are using the Restoration Project, refer to this guide for additional help.