Col du Parpaillon is a high mountain pass located on the boundary between the Alpes-de-Haute-Provence and the Hautes-Alpes departments, in the Provence-Alpes-Côte d'Azur region in southeastern France. It's one of the highest roads of the country.
Set high in the Parpaillon massif within the Cottian Alps of southeastern, just below the highest point sits the infamous Parpaillon Tunnel, at an elevation of 2.650m (8,694ft) above the sea level. It was built by the French Army starting in 1891, to facilitate the movement of troops guarding the border with Italy. Works on the road and tunnel lasted until 1911, although the tunnel was completed in 1901. Once a key route for military supplies, the road was abandoned in favour of the lower Col de Vars, a paved road which could be kept open in winter.
This famous mountain tunnel, one of the highest in Europe, is arched in the middle part and has a total length of 520 meters (1,710 ft). It’s in terrible conditions. The tunnel contains a lot of ice and water and is totally dark. It can be scary and highly recommended to stay outside. Long since abandoned, the spot is both uplifting and yet desolate in its remoteness but the views along the road are breathtaking.
The old military road to the summit is called D29 (southern side) and D39T (northern side). It’s a very challenging unpaved road with narrow parts and some drop offs. It’s totally impassable from October to May. Over a century ago, for many years, this was the highest road in France. The route has fallen into disuse and roughly the top 10 kilometers of both sides are rough, stone filled roads –and the first half is very bumpy. At the high elevations part, the track becomes more tortuous, finally tightening into a seemingly endless hairpin ascent, repeatedly crossing and re-crossing a deep gully gouged by torrents of rain and melt-water cascading down to the valley floor far below. A 4x4 vehicle is required.
The road to the tunnel is 39.6km (24.60 miles) long, running from La Condamine-Châtelard (in the Alpes-de-Haute-Provence department) to Embrun (in the Hautes-Alpes department). The road is steep, hitting a 13% of maximum gradient through some of the ramps. This is a very classic road pass in the Alps and has been used in earlier days in the Tour de France.