Take your time. There’s lots to see, including the “Bank of Zork” (a D&D-universe bank is here), “Atlantis” and “Grail” rooms, a “Smelly” room, lots of pre-Goonies slides, a Coal Mine, a Pengo-esque slide-the-blocks maze, a “Cryptt,” a “Tombb,” a “Foreest”—click to enlarge and get started.
The master cartographer is Stephen Roy, who worked on it over the course of three years, and the map is via Cluster 8’s Flickr.
UPDATE: This is actually a map (see below) of Zork I, a text adventure originally released in 1977. The original DOS version did not come with a map, hence the incredible work you see above. Thanks for the heads up, David Augustyn.
2 Warps to Neptune 
ZORK holy crap lol. I actually played that game. Yup, total text-based. Weird how back then I would literally get goosebumps as I typed in my commands, in anticipation of what was to happen next. I could never get far, though…it seemed that I always “got eaten by a Grue” no matter what path I chose.
Wow – proper folk art.
I have a hand drawn map I did of the caverns in “Below the Root”. No where near as elaborate, but they did save my butt once when I dropped my torch.
It’s a bit more complicated than that- Dungeon / Zork came out on mainframe computers, prior to being released in home versions. The game was too big to fit into home computers of the time, so it was fragmented and its various puzzles were scattered through three different games.
This is the original Dungeon, prior to the split. The bulk of the map formed Zork I, but lots of the little puzzles (sliding maze, volcano, bank, etc) don’t appear in the smaller map. Those ended up in II and III.
As a side project I did a port of the original PDP-10 Zork/Dungeon 616-point version. It closely follows the map above, though this map is for the 585 point version, and missing a couple of puzzles. You can download Windows and Linux versions at https://bitbucket.org/jclaar3/zork/downloads/
I have the best version ever of the 616 point version. text me at “jkapp76 at gmail dot com” and I’ll send you a link to it.