The Caverns of Thracia is an adventure scenario with a background based on Greek mythology which details a dungeon complex as well as a lost city.

Many years ago lizard men used them as a religious center until they were defeated by human worshippers of the death god Thanatos.

The minotaur king controls all the caverns, except for a small portion of the first level that the worshippers of Thanatos have held on to.

[2] The Caverns of Thracia is a very large adventure setting with significant historical background detail provided in the text.

There is a feeling of randomness about Caverns of Thracia, Dark Tower and the others which is not present in the TSR Modules, and one gets the impression that the coherence is incomplete.

"[2] Patrick Amory reviewed Caverns of Thracia for Different Worlds magazine and stated that "this D&D dungeon is an example of Judges Guild at their best.

[7] James Maliszewski of Grognardia called it "a good example of why Judges Guild is remembered so fondly by so many of us who started gaming in the 70s.

"[8] In his 2023 book Monsters, Aliens, and Holes in the Ground, RPG historian Stu Horvath noted, "Along with Snakepipe Hollow (1979) and The Keep on the Borderlands (1979), The Caverns of Thracia share a set of surprisingly similar characteristics, and they represent a kind of culmination of adventure design in the '70s ... Jaquays's intricate, non-linear spaces are the ideal venue for players to star in stories of their own making.