I like Dr Who, but I am not sure how that would relate to a Star Trek related theme (Guardian of Forever) which has its roots in the Fallout series with the Solar Scorcher.
I had though about placing it in the wilderness, I had even scouted a location for it that may have been perfect (the death claw open alcove way up at the northern border) but decided against an open gateway. The images from Star Trek show a wasteland, but I think the gateway was once inside a building, or perhaps a city square of some kind. So, I decided a building with a 'use once' gateway would be better since you cannot use the gateway again after you come back. I made it sort of a 'surreal' experience for the player. You know, where the player starts to think, did it really happen?
I recreated vault 13 from the original layout from the previous Fallout games (which I am a fan of) to give a 3-D experience to those memories. It should be a fun and 'rewarding' experience for the player with a slight puzzle to get through it and escape. In the original, you had to actually 'break' the water-chip which is where the original Fallout game began. Funny, actually.