Pic du Midi Observatory

The observatory on the Pic du Midi de Bigorre is one of the most spectacularly placed scientific stations in the world: a cluster of white domes and terraces on the summit of a detached Pyrenean peak at 2,877 m, standing out so far from the main chain that on a clear day the view runs along the whole range. Its height and isolation made the summit a place where, for more than a century, astronomers came to push the limits of what could be seen from the ground.

The idea came from General Charles de Nansouty and the engineer Célestin-Xavier Vaussenat, who set out to build a mountain-top weather station and observatory in the 1870s with the backing of the Société Ramond. Work began in 1878, and the materials had to be taken by train to Bagnères-de-Bigorre, then by ox cart to the Col du Tourmalet, and finally carried up the last slopes by hand. The buildings were completed in 1881, and in 1882 the station was handed over to the French state. Over the next century the summit collected a remarkable record. In the 1930s Bernard Lyot invented the coronagraph here, an instrument that makes it possible to study the Sun's corona without waiting for an eclipse, and made the first films of it. In the 1960s a 1.06-metre telescope funded by NASA photographed the surface of the Moon in detail to prepare the Apollo landings, and in 1980 French astronomers used the site to discover Helene, a small moon of Saturn. The 2-metre Bernard Lyot Telescope, the largest telescope in France, still works on the summit.

For a long time the peak was reached only on foot or by the equipment cableway; a passenger cable car first carried the public up in August 1952, and after a major redevelopment the summit opened to tourism in June 2000. Visitors now share the mountain with working researchers: there is an exhibition space about the history of the site and the science done here, panoramic terraces, and a suspended footbridge twelve metres long that juts out over the void. The surrounding area was recognised in 2013 as an International Dark Sky Reserve, the first in Europe, and evenings with stargazing are part of what the site offers. Seeing the Pyrenees turn pink at sunset and the Milky Way appear over the domes is the reason many people make the trip.

Getting there

The summit is reached by cable car from the ski resort of La Mongie, on the road to the Col du Tourmalet; the ride takes about fifteen minutes. Lourdes is about 23 km away in a straight line, and the nearest airport is Tarbes-Lourdes-Pyrénées (LDE), about 30 km away. Bagnères-de-Bigorre, in the valley below, is the nearest town on the northern approach.