Originally a Nascom 1&2 version of Colossal Cave entitled 16K Adventure, published as early as May 1981 by Michael J. Evis' Syrtis Software and ANCO. (Potentially making this the first UK-authored port of the classic mainframe game for a home computer system)
A 32K version for Nascom was advertised in the July-October 1982 issue of 80-Bus News.
A ZX Spectrum version of the game is advertised in the August/September 1983 edition of ZX Computing and was re-released in 1984 by Micro Gold.
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This is probably the best "proper" version of Adventure for the Spectrum, and certainly the closest to the original I've yet played. Well worth trying out, and IMO rather better than the more famous Abersoft/Melbourne House one.
The Abersoft version was published earlier on the Speccy, but this one has the distinction of being a bone fide, complete, totally orthodox version of WOOD0350, minus the Wizard routines. I have only found a difference, which is the description of the vending machine (labelled "BATTERAMA").