A new book published by the UK Natural History Museum showcases some of the most memorable underwater photographs taken over the last few decades in its annual wildlife photographer of the year competition. Here: Giant gathering by Tony Wu. “The first indication that something extraordinary was going on were the blows, huge numbers of them – the exhalations of huge numbers of whales. Entering the water, the photographer witnessed an extraordinary scene”. (Photo by Tony Wu/Unforgettable Underwater Photography/NHM)

Aiden Haas, left, and Lilli Alcala pose after being crowned Mud King and Mud Queen at the 29th annual Mud Day, Tuesday, July 12, 2016 in Westland, Mich. The event, open to children 12 and younger, was at the Hines Park-Nankin Mills Area west of Detroit. Children 12 and younger were able to slosh around in the pit while participating in mud limbo, wheelbarrow races and other free activities. (Photo by Carlos Osorio/AP Photo)

A man washes his horse as a woman bathes her son at concrete water pens under a flyover in a slum area in Kolkata, India October 21, 2016. (Photo by Rupak De Chowdhuri/Reuters)

The provincial highest chimney collapses as it is demolished by explosives in Shenyang, Liaoning province, April 28, 2014. The 150-metre-high chimney used to be part of a local heating factory, according to local media. (Photo by Sheng Li/Reuters)

Russian President Vladimir Putin visits the Byzantine and Christian museum in Athens, Friday, May 27, 2016. Russia's president is due in financially struggling Greece Friday for a state visit that will include a trip to a 1,000-year-old, all-male Orthodox Christian sanctuary in the north of the country. (Photo by Thanassis Stavrakis/AP Photo)

Water way to go. These incredible images show the moment two brave adventurers decided to body board down Europes longest glacier. Seen carving their way through the icy rivers of the Aletsch Glacier in Switzerland, the pair are seen risking their lives for an adrenalin rush of a whole new kind. Pictured mounted on their body boards as part of a sport known as hydrospeeding, the daredevils risked being carried away by strong currents and even drowning in hidden crevices to complete the winding seven mile journey. But if that wasnt dangerous enough, the duo also ran the risk of being overwhelmed by collapsing glacial lakes that could be released into the river at any moment. (Photo by David Carlier/Caters News)

The Costa Verde hotel. It is a fully outfitted two bedroom, Boeing 727 suite in Costa Rica. Located within tropical rainforest, Hotel Costa Verde’s rather unusual fuselage suite consists of a refurbished vintage 1965 Boeing 727 airframe. The aircraft was part of South-Africa Air in her previous life. Sitting atop a 50-foot pedestal just beyond a majestic national park, the remodelled jumbo jet’s interior is entirely Costa Rican teak panelling with Indonesian teak furniture and also features a private entrance up a river rock.

Daredevil Christopher Gillette writhes around with a huge alligator he has saved from death. He works at a Florida sanctuary that rescues the wild beasts if they stroll into neighbourhoods where residents can legally kill them. To raise cash for the centre at Homestead, staff put on shows to feed and wrestle the alligators. Photographer John Chapa, 41, and girlfriend Adriana Canargo, 30, took these shots. Photo: Assistant photographer Adriana Canargo dives with a wild alligator. (Photo by John Chapa/Barcroft Media)