While doing some research for a project, I came across a number of unusual orienteering maps:
“Trog-O” – In an underground warren of caves, in south London. Article, map.
“Metr-O” – Orienteering above – and in – a major underground station in Italy. Article, map.
“Ship-O” – On three levels of a cruise ship, in Turkey. Article, map.
“Urb-O” – Park orienteering using aerial imagery, in Norway. Article, map.
“Canoe-O” – Orienteering on the water, in the USA. Article, map.
…and “Punt-O” – Navigating a punt around an aquatic orienteering course, a few years ago. Pioneered by Oxford. No map available on the internet, but it is out there somewhere…