There are several good maps I could suggest but I can't remember all their names since it was a while ago since I've played them.. But i'll make an example by suggesting TrenchToast !
Trench Toast is a terrain-based map that features lots of fortifications and sniper positions, as well as a number of canals and trenches for players to use as cover. The new map supports far more players--up to 32--than the original checkpoint map included in Wolfenstein, and it features lots of hidden areas and a wide-open style rather than the streets featured in the other checkpoint map.
An good old RTCW map that's also made for ET.