A festival goer uses a hula hoop, as revelers gather ahead of this weekends Glastonbury Festival of Music and Performing Arts on Worthy Farm in Somerset, southwest England, on June 25, 2014. US metal giants Metallica will play this year's coveted Saturday night headline spot at Britain's Glastonbury festival, organisers announced Thursday. It will be the “Master of Puppets” four-piece's first appearance at the legendary festival, held in south west England, following on from The Rolling Stones' Worthy Farm debut last year. (Photo by Leon Neal/AFP Photo)

Every year National Parks Week gives visitors a chance to celebrate the incredible woodland spaces around the UK. This year the National Parks Week runs from 28 July – 3 August and there are 10 national parks across England to explore. Each one has created a special event to celebrate the National Parks Week, from picnics and treasure hunt in the park to cycle rides, safari or outdoor art exhibition. (Photo by Diana Jarvis/VisitEngland)

“El rio mas bonito del Mundo”, the most beautiful river of the world, the “River of five colors”, the “Rainbow River”, or even the “Escaped from Paradise”, are the shimmering appellations that Colombians give to Cano Cristales, a small stream located in the heart of the Macarena National Park, 150 km (93 miles) south of Bogota. Photo: A waterfall is seen at the end of the rainy season, in August, when the water level finally decreases, in the Cano Cristales RIver in the Sierra de la Macarena in Colombia. It has become covered with a bright pink endemic aquatic plant, Macarenia Clavigera. (Photo by Olivier Grunewald)

A Nepalese army solder stand next to a horse during the “Ghodejatra” Horse Race festival, which is organised by the Nepal Army, in Kathmandu, Nepal, April 7, 2016. Ghode Jatra, the horse racing festival of Nepal, celebrated on the New Moon day of mid March or early April is among the important celebrations of the Kathmandu Valley. Grand horse parade including various acrobatic style of shows are performed by Nepal military at Tundikhel-a fenced parade ground located in the heart of Kathmandu city. (Photo by Navesh Chitrakar/Reuters)

One of the two wooden rafts of the Kon-Tiki II expedition is prepared at the port of Callao prior to the departure to Pascua island in Chile, in Callao, Peru, October 30, 2015. Fourteen men from various parts of the world set out on rafts to commemorate the Norwegian navigator Thor Heyerdahl expedition 68 years ago. The original raft crossed the Pacific Ocean from South America to the Polynesian Islands. This rafts are a replica of ships used 6,000 years ago, but will be equipped with solar panel. (Photo by Mariana Bazo/Reuters)

“The giant clam, Tridacna gigas (known as pā’ua in Cook Islands Māori), is the largest living bivalve mollusc. T. gigas is one of the most endangered clam species. It was mentioned as early as 1825 in scientific reports. One of a number of large clam species native to the shallow coral reefs of the South Pacific and Indian oceans, they can weigh more than 200 kilograms (440 lb) measure as much as 120 cm (47 in) across, and have an average lifespan in the wild of 100 years or more”. – Wikipedia

Photo: Tridacna Gigas, or Giant Clams spew water as a traditional fisherman passes by a small sanctuary on January 23, 2004 near Bolinao in the Northern Philippines. The clams, prime builders for coral reefs and providing shelter for spawning fish and other marine life, are exposed by low tides in the sanctuary. Overfishing and pollution throughout the country are not only threatening food security, but are also starting to choke one of the few working clam sanctuaries in the world. (Photo by David Greedy/Getty Images)

In this Thursday, August 17, 2017 photo, a troupe charges and fires their rifles during Tabourida, a traditional horse riding show also known as Fantasia, in Mansouria, near Casablanca, Morocco. Thousands gathered recently in Mansouria, a small town south of the capital Rabat, to attend one of the oldest festivals in Morocco. Nineteen horse troupes came from different parts of the kingdom to celebrate a three-day event that blends courage, skill and tradition. (Photo by Mosa'ab Elshamy/AP Photo)

Double tornadoes, lightning storms and rotating supercells – this is what it's like to chase storms for a year. These dramatic images show apocalyptic weather throughout 2014 from a lightning storm to a pair of rainbows. Roger Hill, 57, has been chasing storms in the United States for thirty years and runs a tour operation with his wife Caryn. Here: a hailstorm rolls over fields, on July 22, 2014, in South Dakota. (Photo by Roger Hill/Barcroft Media)