Massive queues are forming on Mount Everest as hundreds attempt to scale the world's highest peak. Pictures showed climbers walking in a long line as they gear up to ascend to the nearly 29,000-foot-high mountain this month, during the much-anticipated window of good weather on Everest. The so-called 'traffic jams' have been forming between Everest Camp III and Camp IV, an extremely perilous high-altitude stretch known as the Death Zone, where visitors rely on supplemental oxygen. Climbers attempting to cross the area have a short window of time to make it through before their bodies begin to deteriorate due to the high altitude and freezing conditions. Almost 500 foreign climbers were granted permits to scale the Nepalese mountain this year and gathered at the base camp last month to begin their journey. After weeks of acclimatising to the altitude, a wave of them set off on Sunday to scale the Nepalese mountain. Several have already reached the top, but the highest number of summits is expected today or Wednesday, according to adventure sports publication Explorers Web. But safety concerns have already been raised over the 'traffic jams' that have formed on Everest, which have been primarily caused by a huge unstable glacier that had previously blocked the route up the mountain from Base Camp. Climbers walk in a long queue as they head to the summit of Mount Everest in the Solukhumbu district, also known as the Everest region of Nepal, on Monday The so-called 'traffic jams' have been forming between Everest Camp III and Camp IV, an extremely perilous high-altitude stretch known as the Death Zone'Icefall doctors' – the elite guides deployed by the Sagarmatha Pollution Control Committee, or SPCC – opened the icefall route on April 29, but issued a warning, saying: 'The serac has multiple cracks and may collapse at any time. 'SPCC strongly urges all expedition operators and climbers to exercise extreme caution.'The serac is part of the Khumbu Icefall, a constantly shifting glacier with deep crevasses and huge overhanging ice that can be as big as ten-story buildings. It’s considered one of the most difficult and trickiest sections of the climb to the peak.A falling serac triggered an avalanche over the Khumbu Icefall in 2014 that killed 16 Nepali guides and workers.This year, the team is reducing loads, minimising exposure time, carefully timing movements through the icefall, and relying on highly experienced Sherpas and guides for risk assessment.Other expedition operators are also cautioning their members about the risks and closely monitoring the situation.Mountaineer Jon Krakauer, who did Everest in 1996, warned that while it is much safer to climb the peak nowadays, 'there is still tremendous risk from mass casualty incidents'.Speaking to CNN, he said: 'Everest is still dangerous, this year especially,' explaining that while over 400 climbers were given permits, they will be accompanied by local guides, meaning that the number of people on the mountain has to be doubled. 'Each of those climbers has a Sherpa with him and sometimes two. So there will be 1,000 climbers going through the summit in the next ten days, 15 days.''These 1,000 climbers are all going to be heading for the summit in the same brief windows, and that's dangerous. There's likely to be a lot of crowding, which makes me nervous,' he added. Earlier this month, Nepali guide Phura Gyaljen Sherpa died after falling into a crevasse, bringing the season's tally among Everest climbers to three. The 21-year-old was killed after slipping on the snow and plunging near Camp III on Everest, located at about 23,620ft, said Nisha Thapa Rawat, ​a tourism department official. Almost 500 foreign climbers were granted permits to scale the Nepalese mountain this yearAnother ​Nepali climber, Bijay Ghimire ⁠Bishwakarma, 35, died during an acclimatisation exercise at the mountain's Khumbu icefall, while 51-year-old Lakpa Dendi Sherpa died on his way ​to base camp early this month, hiking officials said.There has been growing concern about the rapid melting of glaciers due to global warming and climate change. UN Secretary-General Antonio Guterres flew to a mountain in Nepal in 2023 and warned of the devastating extent of glacier melt in the Himalayas.