Marathon generally refers to MTB marathons in my humble experience.
My girlfriend and I just ordered new bikes at a LBS in Zurich on saturday. This guy is offering 15% off bikes ordered before the end of December which is quite a good discount by Swiss standards. He will build you a semi custom bike, pick your frame and he will get a build kit together for you to build the bike you want.
I personally was looking for a bike that I could do marathons on, but could still take to a bike park or do some alpine descents on without shaking my back teeth on, so managed to put together a 12.5kg bike with 140mm of travel (A little heavy for a pure marathon bike, but I just want to participate not win!) Most marathon bikes are hardtail or have only 100mm travel at the back I think he could put something together for you without a problem.
www.mountainthrill.ch is his website, I can highly recommend him. My girlfriend bought her first bike off him, and now we have just ordered two shiny new bikes.