Adventure (1975-1977)

Teletype output of Will Crowther's original version of Adventure.

In the mid 1970s, programmer, caver, and role-player William Crowther developed a program called Adventure. Crowther, an employee at Bolt, Beranek and Newman^[35] (a Boston company involved with ARPANET routers) used the company's PDP-10 to create the game, which required 300 kilobytes of memory.^[35][36][37]
The game used a text interface to create an interactive adventure through an underground cave system, based on part of the Mammoth Cave system in Kentucky.^[35] Crowther's work was later modified and expanded by programmer Don Woods using the SAIL computer at Stanford,^[35] and the game became wildly popular among early computer enthusiasts, spreading across the nascent ARPANET in the late 1970s.
The combination of realistic cave descriptions and fantastical elements proved immensely appealing, and defined the adventure game genre for decades to come. Swords, magic words, puzzles involving objects, and vast underground realms would all become staples of the text adventure genre.
The "Armchair adventure" soon spread beyond college campuses as the microcomputing movement gained steam. Numerous variations of Adventure appeared throughout the late 1970s and early 1980s, with some of these later versions being re-christened Colossal Adventure or Colossal Caves.^[36][38][39]