Vilcabamba addon - Half-Life

Vilcabamba: HL singleplayer by [Kasperg] YUGO
Slightly based on the second level of Tomb Raider

extract the bsp into your valve/maps folder and play

This singleplayer map takes place in a recently discovered (and well preserved) ancient underground city somewhere in the Andes mountains.
Scientist at Black Mesa discovered a very strong energy signal coming from there and established a base to investigate. Unfortunately, the army is also aware of this discovery and sent a squad.
Contact has been lost with the scientific team so you must go and investigate the events.

This map has been made in 5 days and 3 nights.
R_speeds are very high so don't run this in software mod or in a crappy PC
If you think something is too difficult to accomplish in this map, then there's probably another way.

All texture credits go to by Matthew Hill, who redesigned CORE's Tomb Raider textures
Resonantedge.com