To date, ‘Caratsch’ still holds the record for the best time over the 136-corner route

Between 1922 and 1934, the Swiss ‘Klausenrennen’ was by far the most demanding hillclimb of its day. It was not only Caracciola who accepted the challenge: the likes of Hans Stuck and Tazio Nuvolari also braved the 21.5km route, snaking through the hills from Linthal up to the base of the Clariden mountain.

To date, ‘Caratsch’ still holds the record for the best time over the 136-corner route. The German stormed up the hill in his fire-breathing Mercedes W25 Grand Prix car, posting an incredible time of 15 minutes and 22.2 seconds.

Even though ex-DTM racing driver Roland Asch has driven some valuable cars in his time, none are in the same league as the W25 he’s about to pilot – being the only surviving example in roadworthy condition, it’s thought to be worth around £35m. It ended up on the Klausenrennen start line through a collaborative effort between Mercedes and IWC and, as the start nears, Asch admits to feeling a little nervous. “It’s a very special thing!” he shouts, all but drowned out by the thunderous eight-cylinder engine.

On his return from a practice run, Asch is both relieved and overjoyed: “I’ll probably never get a chance to do that again. Driving in Caracciola’s tyretracks was amazing.” The spectators were equally enchanted – they’re used to seeing such a route and car combination only in monochrome photos, not taking place live before their very eyes.

Photos: IWC