Yeah, I was going to sugges CTF-Zeitkind (insert version number here) if nobody had mentioned it. That thing is huge! I once tried to take inventory on it, and I came up with 17 rocket launchers, for one thing. I believe that there are also 12 superhealths and 9 shieldbelts in that map.
Anyway, it's a pretty cool map. It's made up of two symmetrical bases with an asymmetrical city between them. I always thought that Run.umx was made for small and fast maps, but it fits this map rather well.
BTW, I've also heard that CTF-Aquamarina and DM-Timerip are pretty large, but I've never checked them out. Can anyone give me more info about them?