I wrote this to my Trope Bingo prompt of “Crossover”, and it came in at 1,925 words. I believe that it stands on its own, but it is directly related to a piece I wrote back in 2014 that is only on Livejournal and is called “Firenze”.
If Bhargarbh was anything, it was an interchange. It wasn't a space between worlds, although those did exist, but it was a small, finite world with many doors linking it to other worlds. Roald Dhogassohn had arrived here through a door from Maerche, which wasn't unusual because Maerche had doors to lots of other worlds, but Bhargarbh was unusual as a destination for one of those doors because most of the worlds you accessed through a door were alternate versions of each other. A series of worlds all much the same as each other with a few significant variations, like different peoples, more or less magic, asteroid strikes, or technology choices. Bhargarbh had a surface area that was sixteen to twenty kilometres across, depending where and in which direction you measured it. It had a slightly orange sun, a day length of 24.7 hours by the time keeping standards of Roald's homeland, and it was surrounded by a two and a half metre tall wall of quartz. Rumour suggested that there was nothing beyond the quartz – visitors were dissuaded from looking. Roald didn't pretend to understand it, he just used the place as a quick, safe way to get from one world to the next.