From publisher blurb:
The Lost City was the first fully developed “campaign” adventure and location sourcebook for the post-apocalyptic role-playing game, Darwin's World. This is an updated version of the adventure for Darwin's World 2nd Edition. The Lost City is no longer a “stand-alone” adventure; however, as many creatures first introduced here have been reworked and published in other Darwin's World supplements (most notably Metal Gods). In addition, a new sequel, Return To The Lost City (Secrets of The Second Dome) continues to expand on the Lost City setting and provides more opportunities for adventure in the otherworldly underground ruins.
A party of four to six characters of level 1-3 should be able to meet and deal with the initial dangers of the Lost City, but later dangers will require characters of much greater levels. The very nature of the city permits characters to carve out a niche or base of operations; permitting a protracted campaign to explore the city and encounter its bizarre troglodilian peoples.
The Lost City details in full the legendary “Sunken City”, formerly Bakersfield, California, as described briefly on pages 354-355 of the Darwin's World 2nd Edition rulebook. The term “Lost City” is used synonymously to describe the same location.