The riders start near the Millau Viaduct, which is the tallest cable-stayed road bridge in the world, and set off for a hilly stage. Well before the halfway mark they tackle the Col de Sié. This is the first of two of the biggest obstacles en route to the fortified town Carcassonne, the other one is the Pic de Nore.
The Col de Sié looms at kilometre 60. It is a 14.2 kilometres climb with an average gradient of 4.1%. The first half is steepest, while the second half is marked by some flat sections.
Another rolling section takes the riders in some 50 kilometres to the foot of the Pic de Nore. The first 7 kilometres are averaging 7.5%, while the seventh kilometer is steepest at 9.4%. The next 4 kilometres go up at 5.4%, while the climb flattens out to a false flat just before the summit, which is crested with 41 kilometres left to race.
The finale is played out on the flat.
The last time the Tour visited Carcassonne was in 2016. The 11th stage left here for a stormy race on the roads to Montpellier. Chris Froome and Peter Sagan attacked in the finale with the World Champion winning the stage honours and the Briton putting some time into his opponents.
Tour de France 2018 stage 15: Route maps, height profiles, and more
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