These black-and-white photos are taken from the new book “Armoured Warfare in the First World War 1916 – 1918” by Anthony Tucker-Jones and published by Pen & Sword Military. Here: British troops hitch a ride on a Mark IV after the massed tank fleet spearheading attack at Cambrai on November 20, 1917. (Photo by Anthony Tucker-Jones/Mediadrumworld.com)

“Hippo Chase”. As we approached the camp the Selinda Reserve of northern Botswana our boat passed by a hippo resting in the water. I turned around to look back at the boat's wake and saw the hippo charging after us! The hippo must've been tired from an all-nighter because he was angry. He rose way up out of the water three times trying to chase our boat! He was coming at us with such force that he created a wake of his own. Photo location: Selinda Reserve of northern Botswana. (Photo and caption by Curtis Simmons/National Geographic Photo Contest)

“The Eiffel Tower (French: La Tour Eiffel, nickname La dame de fer, the iron lady) is a puddle iron lattice tower located on the Champ de Mars in Paris. Built in 1889, it has become both a global icon of France and one of the most recognizable structures in the world. The tower is the tallest building in Paris and the most-visited paid monument in the world. Named for its designer, engineer Gustave Eiffel, the tower was built as the entrance arch to the 1889 World's Fair. The tower stands 324 metres (1,063 ft) tall, about the same height as an 81-storey building”. – Wikipedia

Photo: French engineer Alexandre Gustave Eiffel (1832–1923), left, poses high on the steps of the completed Eiffel Tower, which he designed for the 1889 Paris Exposition. (Photo by General Photographic Agency/Getty Images)

“Doctor fish is the name given to two species of fish: Garra rufa and Cyprinion macrostomus. Other nicknames include nibble fish, kangal fish, physio fish and doctorfishen; in non-medical contexts, Garra rufa is called the reddish log sucker. They live and breed in the outdoor pools of some Turkish spas, where they feed on the skin of patients with psoriasis. The fish are like combfishes in that they only consume the affected and dead areas of the skin, leaving the healthy skin to grow, with the outdoor location of the treatment bringing beneficial effects. The spas are not meant as a curative treatment option, only as a temporary alleviation of symptoms, and patients usually revisit the spas every few months”. – Wikipedia

Photo: Visitors to the Aqua Sheko fish therapy spa have their feet exfoliated on June 24, 2010 in London, England. Customers sit with their feet in a tank filled with 100-150 Garra Rufa fish which remove any dead skin by nibbling and sucking. A half hour session is then followed by a foot massage. (Photo by Peter Macdiarmid/Getty Images)

“Wells Cathedral is a Church of England cathedral in Wells, Somerset, England. Built between 1175 and 1490, Wells Cathedral has been described as “the most poetic of the English Cathedrals”. The Wells clock, an astronomical clock, is located in the north transept. The surviving mechanism, dated to between 1386 and 1392, was replaced in the 19th century, and was eventually moved to the Science Museum in London, where it continues to operate. It is the second-oldest surviving clock in England”. – Wikipedia

Photo: The clock face of world's oldest continually-working mechanical clock is seen as it is hand wound for the very last time on August 21, 2010 in Wells, England. (Photo by Matt Cardy/Getty Images)

Shepherds lead their sheep through the centre of Madrid, Spain, Sunday, October 25, 2015. Shepherds have guided a flock of 2,000 sheep through Madrid streets in defense of ancient grazing, droving and migration rights increasingly threatened by urban sprawl and modern agricultural practices. Tourists and city-dwellers were surprised to see the capital's traffic cut to permit the ovine parade to bleat bells clanking its way past the city's most emblematic locations. (Photo by Daniel Ochoa de Olza/AP Photo)

Looking for a reason to visit the Philippines? This mermaid school should do the trick. No, seriously, there’s an actual school that will teach you how to be a mermaid. It’s called the Philippines Mermaid Swimming Academy. (Photo by Philippine Mermaid Swimming Academy/Exclusivepix Media)

These stunning images reveal the remains of a more than century-old sunken ship that has been preserved beneath freezing Lake Superior. The ship looks almost exactly the same as it did the day it sunk beneath waves all those years ago. At 60 meters long (approximately 198 feet), the «Gunilda» sunk after it struck some rocks and was not saved. Now, these stunning images have been captured 107 years after the sinking when a small group of divers revisited the vessel. (Photo by Becky Kagan Schott/Caters News Agency)