Between Roquebillière and Saint-Martin-Vésubie, the valley road tightens and rises, and the scenery stops being merely pleasant. The river drops into a narrow gorge, the slopes steepen into dark chestnut and pine, and the villages that were built on spurs above the water start to look like they were fitted into the gaps. This is a landscape that rewards a rider who slows down, partly because the road demands it and partly because there is a great deal to look at.
One small detour is worth a lot. The hamlet of Venanson, perched on the slope above the road, has a little chapel dedicated to Saint Sebastian, whose walls are covered with late-fifteenth-century frescoes painted by Jean Canavesio, a painter from Piedmont. The pictures show scenes from the saint's life, vivid and a little rough, and they were meant to protect the village from the plague. The chapel is usually kept locked, so you may have to ask at the village or check the hours.
The road itself is a series of tight bends and short straights following the river, with a surface that varies from smooth to patched. After the floods of October 2020, parts of it were washed away and rebuilt, and some sections are newer than the rest. Rockfall and gravel in corners are common, particularly after rain, and there are narrow points where a tour coach can fill the whole lane, so keep to your own side and watch the mirrors on blind bends.
The air here carries the smell of chestnut leaves, wet stone and cold water, the sort of alpine freshness that makes the coast feel a long way away. In autumn, the chestnut woods turn the slopes gold and brown, and the local people go out to gather nuts. In summer the shade is welcome, and the river offers a few spots where a swim in cold, clear water is possible if you scramble down.
For fuel, do not rely on the valley. Roquebillière and Saint-Martin have little, and Contes, over twenty kilometres south, is the sure choice, so plan your tank accordingly before heading up.