Marking the 40th anniversary of the Vulkan Express tourist train the Brothaltalbahn staged a Bahnfest over the weekend of 26th/27th August with a visting steam locomotive from the Sauerländer Kleinbahn supporting the lines own Mallet steam locomotive 11sm.

Brohltalbahn Mallet locomotive 11 moves forward over the crossing for the junction between the main and passing tracks at Oberzissen.
27 August 2017

The Brohltalbahn is a metre gauge railway between Brohl am Rhein and Engels in the Eifel. Still carrying some freight traffic the route is best known today for its tourist train, the Vulkan Express. http://vulkan-express.de/en/

Brohltalbahn 11sm is a compound Mallet type locomotive with the rear high pressure engine fixed with frames outside of the wheels to the boiler and main body of the locomotive while the front low pressure engine is arranged to pivot to allow sharp curves to be negotiated.
A Humboldt type M.105 locomotives 11sm was built in 1906, works number 348, a duplicate of locomotive 10sm (built 1904) which the Brohltalbahn had obtained from the Bergheimer Kreisbahn. In the 1960s purchase of diesel locomotives made the steam locomotives surplus to the lines requirements, however while the newer 12sm was scrapped (older 10sm having been scrapped in 1934) 11sm was kept in reserve.
Purchased by the DGEG in 1968 11sm was displayed at Schmalspur-Museum Viernheim from 1975, but was returned to Brohl in 1989 when the museum closed. In the autumn of 1998 the community supporters of the Brohltalbahn, Brohltal-Schmalspureisenbahn e.V. (IBS) bought the 11sm from the DGEG and restoration to operating condition began in 2009. In 2015 11sm was returned to service on the Brohltalbahn, hauling the Vulkan Express from Brohl to Oberzisssen on selected steam weekends.