So, I didn't so much make a map as a transit station. I mean, seriously, you couldn't fit all those cool places on one map. And besides, Hogwarts is Unplottable. Obviously, this station is found in the alternate dimension at the MacArthur BART station, because that's the only place spacious enough for that number of tracks to overlap. And the Muggles can't see it because they don't look properly.