The Karwendel Bahn runs primarily in a south-north direction. It extends from the Inn valley of Innsbruck to the Mittenwald, then West and North to Garmisch-Partenkirchen and on to Munich.
In 1928 the Bavarian Group Administration commissioned the building of new coaches specifically for this route: lightweight coaches with centre aisle and larger windows, aimed at the tourism market. They were painted in a new paint scheme – Dark Blue body (possibly RAL 5013 or 5011) with a light, bright blue window strip (possibly RAL 5012 or 5015). There were the following:
Five B4üe Bay 29 (later DB Aye 602) Bachmann-Liliput L364530
Seven C4üe Bay 29 (later DB Bye 654) Bachmann-Liliput L364531 & L364532
One Pw4üke-28 Bachmann-Liliput L364550
Locomotive power was BR E16, (formerly Bay ES1) Arnold 2449
For the Olympic Games in 1936, the DRG ordered an additional 29 coaches comprising:
Eight ABC4üe-32 (later DB AByse 619)
Twenty One C4üe-32 (later DB Bye 658)
Modelling in HO: There was an equivalent set of cars in HO from Bachmann-Liliput, numbers unfortunately unknown.
WWII saw traffic stopped and after the war, the cars were repainted in standard DB green and used in E-zug compositions.
There is a preserved A4y-29b (formerly B4üe Bay 29) 25001 in the Bavarian Railway Museum in Nördlingen