Fallout 1 -> Glow
Before you set out, make sure you have one rope and three anti-rad tablets in your inventory. Radaway is also a good idea. Approach the location on the world map, but don't enter it. Stop half a tile away and take two anti-rad tablets. This will increase your radiation resistance. Next, hold the rope in one hand, the third tablet in the other, and when you enter the glow map, take it. You'll see a crater there. Move quickly—run.
At the end of the crater, there's a metal beam you should use the rope on. Climb down. Don't approach the elevator yet, but go around it and run to where the man in the armor is lying next to the computer. He'll give you the Brotherhood disc you need to join and a yellow access card. Be careful—the door is trapped. Search all the corpses and all the cabinets; there's plenty of time. And if you haven't joined the Brotherhood yet, leave.
The elevators in the Glow lead down to the heart of the bunker, but all the doors are trapped and locked. You must repair the generator and find the supercomputer, which will tell you about the beginning of the war. There are also many holodisks there, containing various experiments and histories. This is how we learn about the Mutant Military Base and that the Master is Richard Grey, who once worked there and was infected with the FEB 2 virus.
A lot of interesting information and weapons can be found in the Glow, but don't play chess with Skynet, as the radiation will always work against you. The more time you spend in the Glow, the greater the risk of exposure, so keep that in mind.
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