Alternate Source, TheThis was a very early company (beginning of 1980s?) which made a variety of things for the TRS-80 (usually named with TAS as an acronym). One of their products was _The Adventure System_, which was basically a Scott Adams adventure system. It could play his adventures and had support for writing your own. They also published at least two adventures of reasonable size with the package, and there were at least 25 more distributed in a package.
For more information, see Adventure International.
Adventureland was created by Hans Persson and is now maintained by Stefan Meier.
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