A little backstory, I've only played Fallout 3 and New Vegas but I've loved both, one of the main reasons is roaming around and finding all the locations, occasionally stumbling across a strange and/or interesting one.
Now I've recently watched Goldfinger and I had the idea that in the next or a subsequent Fallout game they should include Fort Knox as a location, imagine having to fight through heavily armoured ghouls and other creatures, traverse the building and finally make your way into the vault and to be rewarded with gold bars - much like Dead Money I know but it's more a surprise location you find instead of the whole plot.
To give this some discussion I'll ask two questions:
1 - Do you like the Fort Knox idea?
2 - What landmark would you like to see in a Fallout game, not a location but a specific building or statue or something like that?