British holidaymakers were trapped after 50-tonne boulder lined roads . falling rocks fell off ski resorts near Thorens , Les Menuires and St Martin . Thousands of skiers participated in a 50-mile hike in the French Alps . it was ruled too dangerous for large vehicles to use Friday morning .
British holidaymakers were trapped after 50-tonne boulder blocked road . Falling rocks cut off ski resorts Val Thorens , Les Menuires and St Martin . Thousands of skiers stranded in a 50-mile tailback in the French Alps . Road was ruled too dangerous for large vehicles to use Friday morning .