This is one of the most famous passes in the north French Alps, but mostly for the nice scenery and strategic location and not so much for being a hard pass, which it is not. The south climb starts in Flumet (908m) (or possibly down in Ugine) on the way up/down to (Seuil de) Megève (1107m). The last part of the climb on this side is a nice climb in classic style, but it is not so long or steep.

The climb from the north starts in Les Converses (1214m) (above La Clusaz) if you come down the Col de la Croix Fry (1467m) and/or Col de Merdassier (1496m) and is a short and easy climb from there. If you came over the Col de la Colombière (1607m) you will start the climb at after the bridge at Le Grand-Bornand (885m) (via Col de Saint-Jean-de-Sixt (959m)).

You could also start the climb up all the way north at Saint-Pierre (490m) near Bonneville or up northwest at Thônes (Pont du Villaret) (640m) if you come from Annecy. Just longer ascents but not really adding much to the problem of climbing the pass otherwise.