The Col du Parpaillon is a high mountain pass at an elevation of 2.780 metres (9,120 ft) above the sea level located in the Cottian Alps of southern France in the Parpaillon massif. The pass connects the Ubaye valley in Alpes-de-Haute-Provence department with Embrun in Hautes-Alpes. It's one of the highest mountain roads of Europe.
The most famous part of the road is the Parpaillon Tunnel, located below the pass at an elevation of 2.637 metres (8,652 ft) above the sea level. It was built by the French Army starting in 1891, with work on the road and tunnel lasting until 1911, although the tunnel was completed in 1901. The road to reach the pass is called D29.
This famous mountain tunnel, one of the highest in Europe, is arched in the middle part and has a total length of 520 metres (1,710 ft). Nowadays the tunnel is closed at the end with metal doors. It’s in terrible conditions. The tunnel contains a lot of ice and water and is totally dark. It can be scary, and is highly recommended to stay outside. Long since abandoned, the old trace scaled the wild, rugged Massif du Parpaillon and still appears on larger-scale maps. It's one of the highest mountain roads of the country.
The approach road to the tunnel is not paved and is closed in winter. 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 kilometres of both sides are rough, stone filled roads –and the first half is very bumpy.
To reach the tunnel there are 2 possible routes. From La Condamine Chatelard, the ascent is 17.2 km long and the elevation gain is 1.364 meters. The average percentage is 7.9 %. And from Embrun, the ascent is 27.9 km long with an elevation gain of 1.770 meters. The average percentage is 6.3 %.
The road still remains an adrenaline-pumping journey and is definitely not for the faint of lungs, heart, or legs. A quick glance at the map, at its sheer drops and serpentine twists and turns, confirms that this is no hype. 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.