The Weinberg rail tunnel, awarded by Swiss Federal Railways and the Canton of Zurich, involved the extension of Zurich’s main station railway lines. The 4.2-kilometre tunnel crosses a dense urban area of listed buildings and passes beneath the main branch of the Limmat river. The tunnel, constructed by PraderLosinger without interrupting the station’s operations, was bored using an 11.3-metre mixshield tunnel boring machine and required the conversion of the hard rock double shield to a slurry pressure double shield system to excavate the 280 metres of soft ground. The underground drive beneath the historic Südtrakt station required top-down mining in rock over a distance of 110 metres.