Tour de Suisse 2025 Route stage 4: Heiden - Piuro
The summit of the Splügen Pass marks the border between Switzerland and Italy. To get there, the riders face a total of 35 kilometres of climbing. It begins with a short, steep ramp – not KOM categorised – before continuing at modest gradients to the base of the first official ascent. This climb rises for 10.1 kilometres at 4.5% to the Sufnersee, although the last stretch is slightly steeper: 3.4 kilometres at 5.7%. The road then levels out briefly into a false flat, followed by the main climb up the Splügen Pass: 8.8 kilometres at an average gradient of 7.2%.
The descent is nearly as long as the full climb, and once at the bottom, 9 kilometres remain – all on a steadily rising false flat.
Four years ago, the Giro d’Italia also crossed the Splügen Pass. That time, however, the descent didn’t reach the Val Chiavenna, where Piuro is located. Instead, the riders turned left halfway down to tackle the final climb to the ski station of Motta. Damiano Caruso dropped his breakaway companion Romain Bardet and soloed to victory.
We haven’t yet mentioned the start of the 4th stage – and with good reason. The first 110 kilometres offer little of note, as the peloton rolls south on flat roads towards the Splügen Pass.
Between kilometre 137.4 and 138.3 – the designated Tissot kilometre – riders can contest two sprints worth 3, 2 and 1 bonus seconds each. At the finish, 10, 6 and 4 bonus seconds are up for grabs.
Fancy riding the route yourself? Download GPX 4th stage.
Another interesting read: results 4th stage 2025 Tour de Suisse.
Tour de Suisse 2025 stage 4: route, profile, videos
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