Revelers, covered in coloured powder, celebrate, during a Holi Run Festival in Madrid, Spain, Sunday, April 12, 2015. Thousands of revelers took part in the festival that includes a mini marathon. The festivals are fashioned after the Hindu spring festival Holi, which is mainly celebrated in the north and east of India. (Photo by Andres Kudacki/AP Photo)

Children give “high-fives” as London Marathon runners pass down Deptford’s Evelyn Street, the eight-mile mark of the 26.2 mile course in London, England on Sunday, October 2, 2022. (Photo by Guy Corbishley/Alamy Live News)

A participant takes photographs of his friend while climbing up the stairs during Sky Run, a vertical marathon event, held in the 123-story Lotte World Tower, in Seoul, South Korea on April 22, 2023. (Photo by Kim Soo-hyeon/Reuters)

A runner traverses the route during the Mount Everest Challenge Marathon which winds past spectacular views of Everest and Kanchenjunga at Sandakphu National Park in the month of November 1995 near Darjeeling, India.

To mark World Water Day, on March 22nd Solidarités International and its agency BDDP Unlimited will roll out a campaign to build awareness of the scourge of undrinkable water.