Vatnajökull (meaning Glacier of Rivers), also known as the Vatna Glacier, is the largest and most voluminous Icelandic glacier, and one of the largest in area in Europe. It is located in the south-east of the island, covering more than 8 percent of the country.

Seljalandsfoss waterfall, located in Iceland. Seljalandsfoss is one of the most famous waterfalls of Iceland. This waterfall of the river Seljalandsá drops 60 metres (200 ft) over the cliffs of the former coastline. It's possible to go behind the waterfall. (Photo by HotSpot Media)

Long-tailed mayflies (Palingenia longicauda) at Tisza river near Tiszainoka 135km (84 miles) southeast of Budapest, June 23, 2013. Millions of these short-lived mayflies engage in a frantic rush to mate and reproduce before they perish in just a few hours during “Tiszaviragzas” or Tisza blooming season from late spring to early summer every year. (Photo by Laszlo Balogh/Reuters)

Bangladeshi railway police try to clear line, as thousands of Bangladeshi Muslims gather to board trains to return home after attending three-day Islamic Congregation on the banks of the River Turag in Tongi, 20 kilometers (13 miles) north of the capital Dhaka, Bangladesh, Sunday, January 26, 2014. (Photo by A. M. Ahad/AP Photo)

“Hydrocynus goliath, also known as the goliath tigerfish, giant tigerfish or mbenga, is a very large African predatory freshwater fish. The giant tigerfish is restricted to the Zaire River system, Lualaba River, Lake Upemba and Lake Tanganyika”. (Photo by Tigerfishcamp / Tourettefishing / Bigfishesoftheworld)

An onlooker watches as the “Disney Fantasy” cruise ship is hauled backwards by a tugboat down the Ems River after the ship departed from the Meyer Werft shipyards on January 20, 2012 in Papenburg, Germany. The completed 130,000-tonne ship, which is 1,115 feet long and can accomodate 5,450 passengers, cast and crew, was on its way to the North Sea. (Photo by Sean Gallup/Getty Images)

A man tries to catch a duck during a competition held as a part of the Dragon Boat Festival, known locally as “Peh Cun Festival”, on the Cisadane river in Tanggerang, Indonesia, Thursday, June 9, 2016. The event is celebrated every fifth day of the fifth month on the Chinese lunar calendar. (Photo by Tatan Syuflana/AP Photo)

A devotee offers prayers to the setting sun during the "Chhat" festival at Bagmati river in Kathmandu, Nepal November 17, 2015. Hindus in Nepal celebrate "Chhat", a four-day festival that honours the sun god, by praying at sunrise and sunset, and seek blessings for one's family by giving offerings. (Photo by Navesh Chitrakar/Reuters)