There are a ton of maps. Some are free, some are needed to be downloaded.
All the maps[]
Kino der toten
Five
Dead ops arcade
Nacht der untoten
Shi no numa
Der riese
Veriduct
Ascension
Here is the order I would put them in from best to worst (my opinion)[]
Favorite-------Ascension
2.Kino der toten
3.Der riese
4.Five
5.Veriduct
6.Shi no numa
7.Nacht der untoten
Least Favorite--------Dead ops arcade
HERE ARE LINKS TO THE MAP PAGES FOR MORE DETAILS (abriviated)
Dr
V
SNN
NDU
KDT
F
A
DOA