State-of-the-art technology in nostalgic dress: the Polybahn carries over two million passengers a year from Zurich Central to the gates of the ETH on Zürichberg. At the beginning of 2021, Gilgen was awarded the contract to refurbish the total of twelve sliding doors on the vehicle and four half-height sliding doors in the open outer compartment. "The special thing is that we are not allowed to change the exterior," says project manager Bruno Köchli, explaining the requirements. "In addition, we recently had to measure everything in detail at the cabin builder CWA in Olten to make sure that the original plans correspond to reality," explains Bruno Köchli. For the project manager, the contrasts are particularly exciting: "The Polybahn is a listed building and yet it has to meet the latest standards." The delivery of the installations is planned for the beginning of July.