Boucle cyclosportive B8 - La Route des Lacs

This is the bike loop of the Gérardmer XL triathlon: 31.2 kilometers for 623m of positive altitude difference, run 3 times during the main event. The course features long, flat and uneven stretches, interspersed with three "bumps" that take you from valley to valley, lake to lake.
Starting in Gérardmer, near the casino, you cross the town and take a small forest road to the top of the first bump. You recover on the descent and on the flat alongside Lac de Longemer. Continue on to Lac de Retournemer and climb the Col des Feignes sous Vologne, a 3km climb with sections above 7%. You approach an altitude of 1000m before dropping into the Vallée du Chajoux. The descent is rapid, sheltered by the spruce trees that line this winding stretch. First you pass Lac de Lispach, then Lac de la Ténine. Two kilometers after this lake, at the Pont du Metty, you fork right onto the route de la Courbe, which is very steep in places, with a 17% gradient, and then leads to the summit of the Col de Grosse Pierre. From here, you literally plunge down to Les Bas-Rupts and then Gérardmer, having crossed the short col du Haut de la Côte.