With the completion of the cavern for Limberg 3 in December last year, Austria’s largest power station construction site in Kaprun has achieved the first milestone. At 43 metres high, the facility’s machine cavern would be large enough to accommodate one or the other church building. Deep inside the mountain, below the Limberg dam, it took the engineers months of blasting work to excavate the amply sized ­power station cavern. Measuring 25m wide, 63m long and 43m high, the excavated site is located next to the machine room of Limberg 2. While the concrete pouring work is proceeding inside the cavern, the channels for the turbines’ water supply, the horizontal intake conduit and the pressure shaft are being concrete reinforced and armour-plated. Limberg 3 is a pumped-storage power plant with an overall output ­capacity of 480MW. Like Limberg 2, which went on-line in 2011, it is being constructed completely underground between the two existing reservoirs of Mooserboden and Wasserfallboden (1,672m maximum storage level).