Take advantage of one of the many free parking spaces close to the Cycles Routens customer parking lot, and then head straight for the D523.

This loop is for experienced cyclists only. The first section, along the D523, requires you to be vigilant, as the road is very busy. Once up the champ de la vigne climb, you can relax, but it's your effort that you'll have to manage! The rest of the route is quieter, and the final kilometers reward you with a beautiful, curving descent.

As you ascend, you'll enjoy a breathtaking panorama of the Grésivaudan valley and the Chartreuse massif, which cuts across the horizon to your left. On the way down, and on the terrace alongside the Venon church, you'll have a bird's-eye view of the Grenoble basin, from which the three towers emerge, and beyond to the foothills of the Vercors.

From the Routens cycle store parking lot (reserved for customers), take Avenue Henri Duhamel heading south-east. At the first crossroads, turn left, carefully crossing the avenue, onto the two-way cycle lane* on rue Victor Hugo.

Turn right onto Grand'Rue (D 523), which becomes rue Jean-Jaurès a few dozen meters further on, then rue de la Libération and finally rue Hector Berlioz as you enter Murianette.

Turn right, and you're off on the Champ de la Vigne climb (D 291), which takes you upwards for almost 3km.

Leave the D 291 and continue to the right, via the Chemin du Jappin, which becomes the Chemin de Pressembois. For 3km, you'll enjoy sublime views of the Chartreuse Massif and the surrounding countryside.

Carefully turn right onto the D164, which winds downhill. You'll reach the center of Gières on a 3km stretch of narrow, winding road, but you'll need to keep your wits about you.

Carefully cross Avenue d'Uriage and Avenue de la Combe to take Avenue Henri Duhamel, which will take you back to your starting point.