In the summer of 1973, as Dave Arneson and Gary Gygax worked to complete the manuscript for D&D, Greg Svenson was given a play-test copy of that novel new game. He used those rules to create his own adventure dungeon. Tonisborg is the second oldest Mega Dungeon to come out of the Twin Cities group. Svenson and Arneson placed the dungeon in the world of Blackmoor, where Vestfold  is located today. 

Sadly, several years later all copies of the maps were thought lost or destroyed. The maps came to be known as "The Lost Dungeons of Tonisborg," or "Tonisborg" for short.  Decades later, during production of the documentary, Secrets of Blackmoor, a mysterious set of ten old dungeon maps was uncovered - these turned out to be photocopies of Svenson's originals.   

Now published with extensive background information, The Lost Dungeons of Tonisborg is not like any RPG book you've ever encountered.  Step back into time with one of the oldest dungeon adventures ever created!  

https://www.kickstarter.com/projects/secretsofblackmoor/the-lost-dungeons-of-tonisborg 

https://www.secretsofblackmoor.com/

https://vimeo.com/ondemand/sobfinal 

https://twitter.com/Blackmoor_Film