A short kick-up after the start leads onto a fast section before the riders reach Lana, which is the start of the 24.4 kilometres climb up the Passo Castrin, or Hofmahdjoch. The average gradient sits at 5.6%, but this is a meaningless statistic as the middle section is a prolonged false flat. The last 9 kilometres of the Passo Castrin go up at 8.6%.
The riders descend back into the valley and continue to Dimaro. Instead of going straight ahead to tackle the Passo del Tonale the route turns right and climbs up the Passo Campo Carlo Magno. This is a steady climb of 14.6 kilometres at 6.6%.
Still 66.6 kilometres to go at the top of the Passo Campo Carlo Magno. A long downhill takes the riders to Tione before a 4 kilometres climb at 5% and another descent leads to Cimego. This is were the final haul up kicks in. The 10 kilometres climb to Boniprati slopes at 6.8%. Following a short flat stint at the top the riders fly down a technical drop to the line in Pieve di Bono.
The first three riders on the line gain time bonuses of 10, 6 and 4 seconds, while the intermediate sprint at kilometre 87 comes with 3, 2 and 1 seconds.
Tour of the Alps 2021 stage 4: route, profile, more
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