I dared to take my GPS logger with me on the deathmarch.. This is a 100km (62 miles?) walk that starts at 9PM. You have 24 hours to complete. I was not alone. Some 9000 people joined me, but as far as I can tell from the traces, I was the only one mapping for OSM!
Unfortunately, the last 10km are not on the track. I had to give up due to low blood pressure (almost passed out) and a swollen ankle. Next year, I'll get us those last 10 km.
I hope to enter the whole march as a relation, so that I can maybe convince the organisation of using our map next year.
More information:
http://2008.dodentocht.be
The trace:
osm.org/traces/tag/dodentocht