Grand Som
Mountain Prominent summit in Auvergne-Rhône-Alpes, hiking destination
In the Chartreuse massif, Grand Som has marked trails and limestone ridges, attracting day hikers and those scouting alpine pastures and viewpoints.
Grand Som is a mountain in the Chartreuse massif of the French Alps with a summit at about 2026 metres above sea level. It is part of the Parc naturel régional de Chartreuse.
The mountain offers a compact summit area and alpine scenery typical of the Chartreuse range, used mainly for day hikes and mountain walking. Trails approach the summit from surrounding villages and cols, providing panoramic views over nearby ridges.
The peak has long been part of local alpine use for grazing and seasonal movement rather than a built monument; its routes were formalized as the regional park developed in the 20th century. No major structures sit on the summit.
Grand Som sits in the Chartreuse massif in the Auvergne-Rhône-Alpes region, near Saint-Pierre-de-Chartreuse and northwest of Grenoble. It is within the protected area of the Parc naturel régional de Chartreuse.
- Elevation: Summit elevation is 2026 metres and the peak is within the Parc naturel régional de Chartreuse.
- Access: Commonly reached by marked mountain trails from nearby villages such as Saint-Pierre-de-Chartreuse.
How to Get to Grand Som #
Nearest larger towns include Grenoble and Chambéry. Access usually involves driving on D roads into the foothills of the Chartreuse Massif; most walkers start from nearby trailheads such as Col de Porte or Chalets du Charmant Som, with parking and marked hikes leading to Grand Som.
Tips for Visiting Grand Som #
- If planning to hike, check local trail conditions and weather-alpine weather can change quickly.
- Local maps from the Auvergne-Rhône-Alpes hiking office show routes and estimated times; cell reception can be spotty.
Best Time to Visit Grand Som #
Summer months are best for hiking and accessing trails; shoulder seasons offer quieter conditions but more variable weather.
Weather & Climate near Grand Som #
Grand Som's climate is classified as Subarctic - Subarctic climate with cool summers (peaking in August) and freezing winters (coldest in January). Temperatures range from -5°C to 17°C. Abundant rainfall (1536 mm/year), wettest in November.
January
January is the coldest month with highs of 0°C and lows of -5°C. Significant rainfall (142 mm).
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February
February is freezing with highs of 0°C and lows of -5°C. Significant rainfall (128 mm).
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March
March is freezing with highs of 2°C and lows of -4°C. Significant rainfall (126 mm).
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April
April is cold with highs of 4°C and lows of -2°C. Significant rainfall (122 mm).
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May
May is cold with highs of 10°C and lows of 2°C. Significant rainfall (131 mm).
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June
June is cold with highs of 14°C and lows of 5°C. Significant rainfall (117 mm).
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July
July is cool with highs of 17°C and lows of 8°C. Regular rainfall (86 mm).
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August
August is cool with highs of 17°C and lows of 9°C. Regular rainfall (100 mm).
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September
September is cold with highs of 13°C and lows of 6°C. Significant rainfall (120 mm).
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October
October is cold with highs of 8°C and lows of 2°C. Significant rainfall (143 mm).
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November
November is cold with highs of 4°C and lows of -2°C. The wettest month with heavy rain (169 mm).
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December
December is freezing with highs of 1°C and lows of -4°C. Significant rainfall (152 mm).
