The Route des Grandes Alpes officially begins on the shore of Lake Geneva at Thonon-les-Bains and ends some seven hundred kilometres later on the Mediterranean at Menton. Standing here at the start, with the lake spread out flat and silver in front of you and the Swiss shore hazy on the far side, it is hard to believe that within an hour you will be climbing into proper mountains. That contrast is the whole romance of the thing.
The stop itself is just east of Thonon, towards Publier and Amphion, on the stretch of shore that runs on to Évian, whose spring water ends up in bottles all over the world. Thonon itself is a lively spa town with a funicular linking the upper town to the port, and on its outskirts stands the Château de Ripaille, where Amadeus VIII, Duke of Savoy, retired in the fifteenth century before being elected antipope as Felix V. Between Thonon and Publier, the Dranse river spreads into a wild delta, now a nature reserve full of birds and willow scrub.
Turning south, the route heads up the Dranse valley through narrow gorges, including the deep cleft at the Pont du Diable, and on towards Morzine and the Col des Gets. The road is good but busy in summer, with trucks and holiday traffic, so the first half hour is more about getting into rhythm than attacking corners. After Cluses come the Colombière, the Aravis and the Saisies, and the ride grows steadily bigger. Most of the high passes further south, the Iseran above all, are only open from roughly June to October, so check the status before committing to the full traverse.
As a start or finish, this lakeside area has everything: fuel, supermarkets, bakeries, cafés by the water and plenty of places to stay in Thonon and Évian. Lake Geneva has its own weather, often calmer and milder than the mountains, and on summer evenings the light over the water turns gold, then pink. Finishing a long day here, after descending out of the Chablais, with a cold drink at a lakeside table and the mountains glowing behind you, is about as good as riding gets.