Hunt the Wumpus appeared in Creative Computing, Vol 1, No 5, Sep - Oct 1975, where Yob says he had come up with the game two years previously, after seeing the grid-based games Hurkle, Snark and Mugwump at People's Computing Company (PCC). He later delivered Wumpus to PCC who published it in their newsletter.
ESR says he saw a version including termites running on the Dartmouth Time-Sharing System in 1972-3.
Magnus Olsson, in his 1992-07-07 USENET article <9207071854.AA21847@thep.lu.se>, posted the BASIC source code of what he believed was pretty much the version that was published in 1973 in David Ahl's "101 Basic Computer Games", by Digital Equipment Corporation.
The wumpus lived somewhere in a cave with the topology of an dodecahedron's edge/vertex graph (later versions supported other topologies, including an icosahedron and M"obius strip). The player started somewhere at random in the cave with five "crooked arrows"; these could be shot through up to three connected rooms, and would kill the wumpus on a hit (later versions introduced the wounded wumpus, which got very angry). Unfortunately for players, the movement necessary to map the maze was made hazardous not merely by the wumpus (which would eat you if you stepped on him) but also by bottomless pits and colonies of super bats that would pick you up and drop you at a random location (later versions added "anaerobic termites" that ate arrows, bat migrations and earthquakes that randomly changed pit locations).
This game appears to have been the first to use a non-random graph-structured map (as opposed to a rectangular grid like the even older Star Trek games). In this respect, as in the dungeon-like setting and its terse, amusing messages, it prefigured ADVENT and Zork and was directly ancestral to both (Zork acknowledged this heritage by including a super-bat colony).
[Does "101 Basic Computer Games" give any history?]