Zork is one of the earlist interactive fiction computer games. The first version of Zork was written between 1977 and 1979 using the MDL programming language one a DEC PDP-10 computer. The authors - Tim Anderson,Marc Bland,Bruce Daniels and Dave Lebling - were members of the MIT Dynamic Modelling Group.When Zork was published commercially,it was split up into three games:
Zork: The Great Underground Empire - Part I, later known as Zork I, is an interactive fiction video game written by Marc Blank, Dave Lebling, Bruce Daniels, and Tim Anderson and published by Infocom in 1980. It was the first game in the Zork trilogy and was released for a wide range of computer systems, followed by Zork II and Zork III. It was Infocom's first game, and sold 378,000 copies by 1986.
You also can download Zork I map and walkthrough from here:zork1_walkthrough