If you'll old enough to remember 'ADVENT' and been around the geeks when it was a craze on the ARPA-net in the late 70s. You might find this article which was in my feed last night: https://onezero.medium.com/the-woman-who-inspired-one-of-the-first-hit-video-games-by-mapping-the-worlds-longest-cave-ef572ccde6d2 fun.

For those that did not, it was the world's first adventure game (no graphics, just solving a series of puzzles while wandering through a cave).   It was originally written in Fortran-IV for the PDP-10/20 with a small assembler assist to handle RAD50 for the input.  [FYI: MIT'S Haystack observatory is about 2 miles as the crow flies from my house on the top of hill next over, in the town next to mine, Westford.  Groton, MA is the town after that].

This article is an interesting read (about 20 mins) with stuff I never knew.  I knew a divorced Will Crowthers worked at BBN and wrote the game Adventure for his daughters to play when they visited him.  I also knew that he had been a caver and that the cave in the game was modeled after Kentucky's Mammoth Caves.  I did not know until a few years ago, [from a friend of my wife's, Madeliene Needles] that at some time they were living in Groton (because Crothers' ex-wife was working at Haystack with Madeliene for a while).  As this article tells the story, it was Patricia Crowthers who actually did the mapping work. 

FWIW: As a fun factoid, today, the Stanford version is one of the tests used by the old DEC and now the Intel Fortran-2018 compiler to verify that the compiler can still compile fixed format FORTRAN-IV and ensure the resulting program still works.  And of course, 'packrat Clem;' my own 'advent' map is in my filing cabinet in the basement.  Written on the back of '132 column green bar' computer paper of course.


For the folks that are interested, more good stuff including a number of versions of the code can be found at: https://rickadams.org/adventure/