The GR10 Trail. Brian Johnson

most popular of the three long-distance routes that traverse the mountain range.

      It is an extremely well-waymarked route following good mountain paths, with only a few tough stages with boulderfields to cross and occasional scrambling. Towns and villages are frequent so finding accommodation and supplies is rarely a problem.

      Initially the GR10 follows ridges over the steep rolling hills of the Basque Country before reaching the impressive limestone peaks at the western end of the High Pyrenees. The fantastic Alpine scenery of the High Pyrenees includes a number of tourist hotspots, including the Pic du Midi d’Ossau, Vignemale and Gavarnie. After Bagnères-de-Luchon the GR10 passes into the less-frequented Ariège where the route crosses a succession of deep valleys with occasional returns to spectacular Alpine terrain. As the Mediterranean is approached the Canigou massif dominates the scene and the terrain remains mountainous with the final 1000m peak being only a few miles from the route’s end at Banyuls-sur-Mer.

      The highlight of the GR10 for many walkers isn’t the mountains or the fauna, but the magnificent wildflower meadows, and the associated butterflies, which you will walk through most days on your traverse of the Pyrenees.

The stages

      At 954km in length with a total climb of 53,000m, taking approximately 315 hours to complete, the GR10 is too long for most hikers to do in a single trip and most will break it up into sections and walk it over several years. There are good bus and rail links throughout the French Pyrenees so there is plenty of choice when splitting into sections. For convenience, this guide has been divided into four sections, which fit in well with the rail links. See Appendix A for a route summary table.

      For a fit walker, it would be possible to complete the entire trek in around 45 days by combining stages. This would require some planning ahead to ensure daily distances are realistic and accommodation options fit the intended schedule.

      Section 1: Hendaye-Plage to Etsaut (Stages 1–12)

      As the GR10 leaves the border town of Hendaye on the Atlantic coast it follows ridges over the steep, grassy and wooded rolling hills of the Basque Country. After nine stages there is a rapid transition to the steep limestone peaks at the western end of the High Pyrenees. Section totals: 221km; 11,300m; 68 hours.

      Section 2: Etsaut to Bagnères-de-Luchon (Stages 13–26)

      This is the most spectacular section of the GR10, passing through the High Pyrenees, which rise to over 3000m, crossing high passes that may be snow-covered well into summer. The fantastic scenery in this section means that you will be passing a number of tourist hot-spots, including the Pic du Midi d’Ossau, Vignemale and Gavarnie. Section totals: 253km; 14,400m ascent; 85 hours.

      Section 3: Bagnères-de-Luchon to Mérens-les-Vals (Stages 27–43)

      In this section, the border between France and Spain (or Andorra) is well north of the watershed and the GR10 passes through the Ariège. These mountains aren’t quite as high as the High Pyrenees, but the route crosses a succession of deep valleys cut out by the huge glaciers that flowed north from the Pyrenees in the last Ice Age, meaning that there is a lot of climb. The Ariège has never been as popular as the High Pyrenees so there is often a feeling of remoteness, and facilities for walkers are harder to find. Section totals: 265km; 17,600m ascent; 98 hours.

      Section 4: Mérens-les-Vals to Banyuls-sur-Mer (Stages 44–55)

      The first few days of this section are through spectacular Alpine terrain, after which the mountains become gentler. After the dominating Canigou massif is passed, the terrain becomes drier but remains mountainous, with the final 1000m peak being only a few miles from Banyuls-sur-Mer. Section totals: 215km; 9700m ascent; 64 hours.

      Pont d’Espagne (Stage 18)

The route

      The GR10 doesn’t pass over many summits, but suggestions are made in the route descriptions for climbing many of the easier peaks along the route, often from cols over which the GR10 passes. If you want to climb some of the higher, more difficult peaks you should ask for advice from the guardians of the refuges.

      It would be possible to walk the GR10 from Mediterranean to Atlantic, but this guide describes the route from the Atlantic so that you have the prevailing wind/rain on your back and you have time to acclimatise to the heat before reaching the Mediterranean, with the added advantage that in hot weather the steep climbs can often be done in the shade of early morning.

      The author noted a lot of minor changes to the route between 2014 and 2015 as the Fédération Française de la Randonnée Pédestre (FFRP) are continually trying to improve the route, so don’t be surprised if the route doesn’t always fit with the route description. However route changes are well waymarked and can be followed with confidence.

From the Atlantic to the Mediterranean

      The Pyrenees is traversed by three long-distance routes coast to coast: the GR10, the High-level Route (Haute Randonnée Pyrénéenne, HRP) and the GR11 (la Senda Pirenaica). All three routes provide varied and scenic treks through magnificent, often remote, high or deserted mountains. The GR11 stays higher and is rougher than the GR10, but there is actually more climb on the GR10. Unless you are an experienced mountaineer you should prefer the GR10 or GR11 to the HRP.

      This guide covers the GR10, which remains in France and stays north of the watershed. Well waymarked and following good mountain paths, it is the easiest of the three routes. Although much time is spent climbing up and down steep forested ridges, time is spent above the treeline on every stage. You are able to camp throughout, but it is not a necessity due to the frequent visits to towns and villages and a network of hostel-style accommodation in gîtes d’étape or refuges.

      The HRP, which passes through France, Spain and Andorra, is not so much a walk as a mountaineering expedition. The route is not waymarked, except where it coincides with other routes, and you must expect to get lost! There is a lot of very rough terrain, including some very steep, possibly dangerous descents. Visits to towns and villages are infrequent so resupply is difficult and you will have to camp much of the time. You will spend a lot of time on high mountain ridges with serious risk of thunderstorms and even fresh snow. The HRP is particularly demanding in bad weather or in early summer when snow could mean serious winter mountaineering skills are required. The HRP is a daunting route for the inexperienced but is a magnificent expedition for those with the right experience.

      The GR11 is a well waymarked mountain path, which passes through Spain and Andorra. Like the HRP, it crosses many high mountain passes where there are boulderfields, scree and some easy scrambling at about the maximum difficulty the inexperienced would want when carrying a heavy rucksack. Thunderstorms are less of a problem than on the HRP as you don’t spend long periods on high ridges. Frequent visits to towns and villages mean that resupply isn’t much of a problem. Those who prefer not to camp or bivouac will find that a few of the stages are rather long and that some alternative routes will need to be taken.

Wildlife

      The Pyrenees is a Mecca for the bird-watcher. With the mountain range forming a big barrier to migrating birds, in the spring and autumn they are funnelled along the Atlantic and Mediterranean coastlines and through the lower passes. The casual birdwatcher will be most impressed with the large number of birds of prey.

      The massive Griffon vulture, with a wing-span of about 2.5m, will frequently be seen soaring on the high ridges, while the smaller Egyptian vulture, which is distinctively coloured with a white body, black and white wings, is also likely to be seen. Arguably, the most beautiful bird you will see is the red kite with its deeply forked tail. You can also expect to see black kites, buzzards and honey buzzards, as well as smaller birds of prey such as the kestrel, peregrine falcon, sparrowhawk and rarer birds such as the black-shouldered kite, the goshawk and even a migrating osprey.

      One species, which seems to be thriving, is the Alpine chough, seen in large flocks. This member of the crow family is all black except for a yellow bill and red legs. Wheatear and black redstart