yep it was Adventure by Willy Crowther . he was a caver [ spellunker in the usa i think] and wanted to make a virtual cave network for people to explore. he made it to run on the ARPAnet us military research network that was the forerunner of the internet. he chucked some treasure and a few dwarves in their for a bit of fun. then he went off on vacation. he came back a few weeks later to find very irate techies because so many people were trying to play it the network was crashing.
funny old world - no war, no research, no games