The Ammergaubahn or "Oberammergau Special" is one of the most historic, and scenic, short-line routes in Germany. Built privately in 1900, it was electrified in 1905- Germany's first AC powered line. It's a 24km spur line from the main line at Murnau, via Ramsachleite, Seeleiten-Berggeist, Grafenaschau, Jaegerhaus, Bad Kohlgrub, Saulgrub, Altenau, and Unterammergau to its terminus at the Passion Play village. Rolling stock is currently 440/442s; until a few years ago it was 426s, so neither is a problem. They also ran 141 locos in the 80s-90s. But if you wanted to be ambitious, you could add the 'classic' pre-1987 consist: the elderly (1909!) E 69 locos with two Silberling coaches. Of course, to be authentic you would have to model the trackage and stations as they were before they were altered in 2005-07 (especially the turnaround which was eliminated with the move to push-pull EMUs). But still, this would be a GREAT add-on for all DB (and DRG) fans.
Incidentally, there is operational in-cab video of an E 69 on YouTube, if any modelers are interested: As well as the unusual "Oberammergau maneuver" for turning around:
