The 2-10-0 four-cylinder compound freight locomotive C 5/6 # 2978 from SBB Historic, built by SLM in 1917, is crossing the 25 meter high and 127 meter long Rümlingen viaduct on the Hauenstein north ramp. It is pulling the "Dampf am Hauenstein" train 31726 from Olten via Läufelfingen to Sissach, with the 3 light steel coaches A # 2251, B # 5560 and AB 3721 from the 1950s. The Hauenstein line was opened by the Swiss Central Railway (Schweizerische Centralbahn SCB) in 1858 and was double-tracked at the time, today it has been reduced to one track. The 8 bows limestone viaduct is one of the oldest in Switzerland.