Advent

About

Colossal Cave Adventure (also known simply as "Adventure") was originally written in Fortran IV by Will Crowther and extended by Don Woods; it went on to spawn numerous variants and expansions, including Adventure II, Adventure 3, and Adventure 5/6. This repository provides modern, modular C99 translations of four classic Adventure-family games — Crowther and Woods' original "Adventure," Luckett and Pike's 440-point "Adventure II," David Platt's 550-point "Adventure 3," and Doug McDonald's 551-point "Adventure 6" — and also archives the source code of many other historical variants, including the originals of all four. The C99 translations can additionally be compiled to run on the Z-machine, making them playable in a browser.

How it differs from the original

Unlike many later Adventure ports, which build on Baggett's TADS-based "Colossal Cave Revisited" rewrite, this project translates each game's own original source code (Fortran, RATFOR, or A-code) directly into C, aiming for faithfulness to each historical version rather than adding new content.

Getting started

Each translated game can be played directly in a browser through Z-machine builds linked from the project's site, with separate links for the original Adventure, Adventure 3, Adventure 6, and Adventure II. Compiling the C99 source for the Z-machine yourself requires a patched build of the vbcc compiler's Z-machine backend, applied and built via an included script.

History

The four translated games have decades of documented lineage: Crowther's original Fortran game was extended by Woods, ported to C by Gillogly in 1977, and rewritten in literate CWEB by Knuth in 1998, while Adventure II, Adventure 3, and Adventure 6 were separately developed by Pike/Luckett, Platt, and Long/McDonald between the late 1970s and 1990; the author ported each to C and the Z-machine between 2012 and 2014.

Additional notes

Trivia

David Long's 1980 "New Adventure" (a predecessor to Adventure 6) was thought lost after CompuServe shut down, until an executable copy was rediscovered in late 2025.