A view of trees shrouded in fog on a late summer morning between Tureby and Slimminge on Zealand, Denmark, 10 September 2021. (Photo by Mads Claus Rasmussen/EPA/EFE)

This is the moment fog rolls through a valley making trees disappear as if covered by giant waves in a sea. The fog was rolling in over the sub-alpine mountain range of the Jura Mountains in Switzerland, February 2023. (Photo by Rainer Awiszus-Emser/Solent News & Photo Agency)

Walkers marvel at a fog bow over Curbar Edge, Derbyshire in the last decade of October 2023. The phenomenon is similar to a rainbow, but because the water droplets that cause fog are so small, its colours are very weak. (Photo by Richard Bowring/Animal News Agency)

A young boy walks to his school bus on a foggy day in Dubai on March 14, 2024. (Photo by Chris Whiteoak/The National)

The Last Bell (we mean the bell that informs the pupils about the beginning or the ending of the lessons) is the traditional feast of the Russian pupils who leave the school. The Last School Bell feast occurs in the end of May, when the school year has already finished, but the final examinations have not begun yet. (Read more...)

Sydney Truba, 11, of Melvindale, Michigan lies in a giant lake of mud during Wayne County's 2011 Mud Day event at Nankin Mills Park July 12, 2011 in Westland, Michigan. The annual event consists of 20,000 gallons of water mixed with 200 tons of topsoil. (Photo by Bill Pugliano/Getty Images)

A Nepalese Hindu devotee takes a holy bath as they mark the Mother's Day Festival at Matathirtha on the outskirts of Kathmandu on May 6, 2016. Nepalese Hindu devotees come from across the country to bathe, offer prayers and leave offerings at the Matathirtha Temple during the event, which honours mothers who have passed away. (Photo by Prakash Mathema/AFP Photo)

A glass is checked at the table for China's top leaders before the start of a reception to celebrate National Day at the Great Hall of the People in Beijing, China September 30, 2016. China celebrates its National Day on October 1. (Photo by Damir Sagolj/Reuters)