Celebrities from the entertainment field, including actors Jessica Biel and Emile Hirsch, are climbing 19,340-foot Mount Kilimanjaro to raise awareness about global shortages of drinking water and to raise money for UNHCR and other humanitarian agencies.

The party set off on Thursday afternoon on the Lemosho route and reached the Shira Camp, where they spent their first night at more than 11,000 feet on Africa’s highest mountain. They expect to reach the summit at Uhuru Peak on Tuesday morning before heading back down the mountain.

Those climbing alongside Biel and Hirsch include rapper Lupe Fiasco, conservationist and explorer Alexandra Cousteau, environmentalist Kick Kennedy, award-winning photographers Michael Muller and Jimmy Chin, singer Santi White and actress Isabel Lucas.

Acclaimed musician Kenna, the mastermind behind the “Summit on the Summit,” is leading the hike, driven by the knowledge that his father suffered badly from a water-borne disease while a child in his native Ethiopia. Elizabeth Gore, executive director of global partnerships at the United Nations Foundation, is among others taking part.

The main aim of the “Summit on the Summit” is to raise public awareness about the global clean water crisis, which affects more than 1 billion people around the world, including hundreds of thousands of forcibly displaced people of concern to the UN refugee agency. Many of them live in Africa.

The climb will also raise funds to be distributed through the UN Foundation to several groups, including UNHCR, the Children’s Safe Drinking Water Programme and Water For People and Playpumps International.

The route to the top of the world’s tallest free-standing mountain will take the climbers through savannah, tropical jungle, alpine pasture, moorland, desert, snowfields and glacial landscapes, according to the official expedition website.

“The climb isn’t easy. After 10,000 feet the risk of altitude sickness increases, and fatigue sets in. The symptoms vary from headache, dizziness and nausea to lethargy and euphoria, keeping many from reaching the summit,” the site says, adding: “The last day [on the way up], in sub-zero temperatures and at the highest elevation, will be the toughest.”

The climbers will post blogs, status updates, tweets, photographs and videos at regular intervals as they progress up the mountain. Members of the public can also make donations through the web site, sponsoring every foot of Kilimanjaro.

– unhcr.org