The Three Valleys Steam Railway is a branch railway in southern Belgium that lies west of the River Meuse and passes through the valleys of the rivers Eau Blanche, Eau Noire and Viroin. It was taken over in 1973 by a group of former railway employees who now run trains over 14 km from Mariembourg to Treignes. The branch’s remaining 3 km across the border into France have been abandoned since the line includes a tunnel now used for growing mushrooms. There is a connection with the SNCB/NMBS at Mariembourg where the roundhouse and other facilities for working steam engines have been retained. The company has constructed a large workshop at Treignes. The railway’s own collection includes more than 20 steam locomotives, mostly from Belgium, but there are some from Poland and other countries that operated steam locomotives into the 1970s or even the 1980s. There are several German Kreiglok 2-10-0s, and some important exhibits from the national collection are displayed, if not permanently, at Treignes. These include two examples from the period between 1898 and 1906 when Belgian railways used designs by the Scottish engineer John Ferguson McIntosh (1846-1918), No 16.042 an inside cylinder side tank 4-4-2T, and No 18.051, a 4-4-0 express locomotive that resembles the McIntosh’s ‘Dunalistair’ locomotives built for the Caledonian Railway. There is also the massive No 1.002, built by Cockerill at Seraing, one of a class of 35 designed for the heaviest passenger trains in the 1930s. There are also 13 diesel locomotives and some of the red and yellow autorails (railcars) that worked Belgian branch lines from the 1950s.