Tourism has transformed the pretty, mountain village of Gavarnie; its huge car park is filled by mid-morning. Most visitors run the gauntlet of shops and cafes and then hike up the valley to the immense cirque with its 400m high waterfall; this entails walking the track up through the pine forest and pastures to the Hôtel du Cirque et de la Cascade, where it’s impossible not to stop on the shaded terrace to rest, refresh and refuel; and then onwards up the narrowing path of loose gravel to the base of the waterfall. Hopeful alpine choughs hang around the picnickers.

The flora is rich and includes cross-leaved gentian Gentiana cruciata, Astrantia and dark-red helleborine Epipactis atrorubens. The gentian is the foodplant of the mountain alcon blue Phengaris rebeli but there is no sign of either the butterfly or its distinctive, small white eggs on the plants. The assemblage of plants and butterflies here shows similarities to that found not far to the east in the Ariège, which suggests that they are probably locally common throughout the central Pyrenees. Indeed, the online mapping resource Biodiv’Occitanie provides good evidence that this is the case; for example, it confirms the widespread distribution of dark-red helleborine; it also shows that the mountain alcon blue was recorded here in the Gavarnie valley in 2011.

Unsurprisingly given their names, two endemic butterflies, the Gavarnie blue Agriades pyrenaicus and Gavarnie ringlet Erebia gorgone, are also found here. We find an Erebia butterfly, probably the widespread Piedmont Ringlet Erebia meolans as its white-centered, black spots (ocelli) on the upper wings are too bright to be gorgone. Identification of this large genus of very similar species is tricky and needs more time in the field.