Source SDK | Underground tunnel [Garry's mod map]

Little tunnel connected to the sewer (a section from a larger map; gm_arabtown)
SourceSDK Hammer (HL2) was used ,compiled and then tested in Garry's Mod.
Texture and models are from valve.
Gmod workshop:
" https://steamcommunity.com/workshop/filedetails/?id=2045662374 "