Chamonix trail running marathon, Mont Blanc 4810m, Chamonix, Rhone Alps, Haute Savoie, French Alps, France, Europe

Chamonix trail running marathon, Chamonix, Rhone Alps, Haute Savoie, France, Europe

Chamonix trail running marathon, Mont Blanc 4810m, Chamonix, Rhone Alps, Haute Savoie, French Alps, France, Europe

WIld camping on the GR5 trail or Grand Traverse des Alps near Refuge De Bellachat with views of the Mont Blanc, Chamonix, Haute Savoie, Auvergne-Rhone-Alpes, French Alps, France, Europe

The classic Walkers Haute route from Chamonix to Zermatt the trail leads down into Zermatt with the Matterhorn ahead, Switzerland, Europe

The classic Walkers Haute route from Chamonix to Zermatt the trail leads down into Zermatt with the Matterhorn ahead, Swiss Alps, Switzerland, Europe

Star trail over Mont Blanc range seen from Lac de Cheserys, Chamonix, French Alps, Haute Savoie, France, Europe

Chamonix trail running marathon, Chamonix, Rhone Alps, Haute Savoie, French Alps, France, Europe

Chamonix trail running marathon, Chamonix, Rhone Alps, Haute Savoie, French Alps, France, Europe

France, Alps In Winter, Haute Savoie, Chamonix, Lonesome Skier In Vallee Blanche Trail, Glacier Seracs Behind

Mountain landscape, view of glacier Glacier de Taconnaz, hiking La Jonction, Chamonix, Haute-Savoie, France, Europe

Cairns on the hiking trail, Glacier du Tour, glacier and mountain peaks, high alpine landscape, left Aiguille du Chardonnet, Chamonix, Haute-Savoie, France, Europe

Mountain landscape, view of glacier Glacier de Taconnaz, hiking La Jonction, Chamonix, Haute-Savoie, France, Europe

Climber on hiking trail, Grand Balcon Nord, glacier tongue Mer de Glace, behind Grandes Jorasses, Mont Blanc massif, Chamonix, France, Europe

Three participants of the UTMB are running in the hills of Chamonix. The famous peaks of the Mont Blanc range are in the background. The Ultra-Trail du Mont-Blanc (also referred to as UTMB) is a single-stage mountain ultramarathon. It takes place once a year in the Alps, across France, Italy and Switzerland. The distance is approximately 166 kilometres (103 mi), with a total elevation gain of around 9,600 m. It is widely regarded as one of the most difficult foot races in Europe. It's certainly one of the largest with over two thousand starters. The combined participation in all of the events is approaching 10 thousand runners. While the best runners complete the loop in slightly more than 20 hours, most runners take 30 to 45 hours to reach the finish line.

An elderly woman is running in the hills of Chamonix. She is close to finishing the extremely exhausting UTMB race. The Ultra-Trail du Mont-Blanc (also referred to as UTMB) is a single-stage mountain ultramarathon. It takes place once a year in the Alps, across France, Italy and Switzerland. The distance is approximately 166 kilometres (103 mi), with a total elevation gain of around 9,600 m. It is widely regarded as one of the most difficult foot races in Europe. It's certainly one of the largest with over two thousand starters. The combined participation in all of the events is approaching 10 thousand runners. While the best runners complete the loop in slightly more than 20 hours, most runners take 30 to 45 hours to reach the finish line.

Barbara Zwerger trail running at the Brevent, Chamonix, France, France

Topher Gaylord trail runs in the mountains of Chamonix, France.

Girl trail running in Chamonix around the Chesery lake, Les des Cheserys, Haute Savoie, France.

Girl trail running in Chamonix around the Chesery lake, Le des Cheserys, Haute Savoie, France.

Tim Twietmeyer trail runs in the Mountains of Chamonix, France.