10/5 Mapmakers: Offering map downloads and information on the OBED Marathon level editor.
GameSpot: Chris Hudak review [8.2/10] includes screenshots and downloads. "A distance runner, and with all its perks and goodies should more than tide over the 3-D shooter fanatic."
Marathon Arena: A total conversion for Quake 3 Arena in the spirit of Marathon Infinity.
Marathon Infinity: Official site
Marathon Open Source: Microsoft's own Open Source Initiative, using the GPL'ed Marathon 2 source code, called Aleph One.
Marathon Resurrection: A total conversion for Unreal Tournament in the spirit of Marathon, by Team Unpfhorgiven.
Marathon's Story: Houses the full text of the game series with discussion and speculation.
Scott's Addictions: Review.
The Battle Cat's Marathon Page: Find original Marathon maps, films, Forge tips, and related humor here.