An ultra marathon competitor races past Mont Blanc in France.
CNN  — 

Climbers scaling Europe’s highest peak, Mont Blanc, without having booked a room in one of its shelters could face two years in prison and a €300,000 ($335,000) fine under new rules to limit overcrowding.

Authorities said “huge visitor numbers” on the mountain had led to concerns over “sanitary risks” like water availability and waste disposal problems.

The ban comes into effect Saturday and will remain in place throughout the busy summer climbing season, according to a decree signed by France’s Haute Savoie prefecture on Friday.

It follows the deaths of 11 climbers on Mount Everest this year amid extraordinary images of queues to the summit, prompting fresh concerns over the increased commercialization of mountaineering expeditions.

At 15,771 feet (4,807 meters), Mont Blanc is Western Europe’s tallest and one of its best known mountains, located in the Alps, close to the French border with Italy and Switzerland.

Its peak, in France, attracts more than 20,000 climbers a year. Fifteen people died during attempts on the summit, or on their way back down the mountain, last year according to the Agence France Presse (AFP) news agency.

An investigation by The Atlantic in 2012 found a tendency among tour operators to portray it as more of a “long walk” than a challenging climb – a description which means it can attract casual adventurers unprepared for the risks involved.

The decree was signed on the same day a 25-year-old Slovak climber died after falling 820 feet (250 meters) on the standard route, known as “Route Royale,” AFP reported.

Climbers taking the usual route to the summit, which takes several days, will from now on “only be allowed to do so if they have booked room in one of three hotels: Gouter, Tete Rousse and Nid D’aigle refuges,” said the decree.

It said this was essential to “prevent trouble” from climbers who had not made bookings, including one person who recently “didn’t book a room at the Goûter refuge and threatened the caretaker.”

A public information campaign launched last summer to dissuade crowds from attempting the climb had proved “ineffective,” regional administrator Pierre Lambert told AFP, prompting authorities to tighten restrictions this season.

Mountain guide Adrian Ballinger told CNN that the recent spike in deaths on Mount Everest was, in part, down to a lack of experience among both climbers and tour operators.

He told CNN that while many see Everest as the “ultimate challenge.” the “lower level of experience of the climbers trying to come here, and also of the companies that are trying to offer services on the mountain,” was causing trouble.

He continued, “that lack of experience … is causing these images we see where people make bad decisions, get themselves in trouble up high and end up having unnecessary fatalities.”

Antoine Crouin reported from Paris, Sheena McKenzie wrote in London