Serra da Aboboreira Megalithic Set (Meninas do Crasto) on September 24, 2023 in Baiao, Portugal. Since 1978 that Serra da Aboboreira (Aboboreira Mountains) has been the scene of a systematic study of its archeological values, among which are the monuments known as megalithic. These are funerary monuments designing the landscape. These dolmens were constructed with stones (lithos) of medium or large dimensions (mega), which were laid in a, more or less, vertical position. Over these, it was still placed a lid, also of stone. These containers were covered by an artificial mound of earth and stones (dolmen). (Photo by Octavio Passos/Getty Images)

Volunteers wearing face masks, gloves and protective gear to protect against coronavirus, gather to clean an area of an outdoor book market set up at Red Square with GUM, State Department store, left, St. Basil's Cathedral, center, Spasskaya Tower, second with, and the Kremlin Wall, right, in Moscow, Russia, Saturday, June 6, 2020. Muscovites clad in face masks and gloves ventured into Red Square for an outdoor book market, a small sign of the Russian capital's gradual efforts to open up amid coronavirus concerns. (Photo by Alexander Zemlianichenko/AP Photo)

Girls of University of Cincinnati Stage Grecian Games on April 29, 1921. Garbed in costumes of ancient Greece, fair students of the University of Cincinnati, Ohio arranged a set of Grecian Games for the benefit of the University athletic fund. All of the girl students of the University, who take a great interest in outdoor games and athletics, took part in the games. The fund was greatly increased through the staging of the unique attraction and the girls purpose to give a return engagement. The accompanying photographs show the girl contestants in their Grecian costumes. Photo shows the start of the 100 yard dash. (Photo by Bettmann Archive/Getty Images)

ESA astronaut Tim Peake posted this stunning image on his social media channels, commenting: “Station passed through magnificent aurora Australis last night”. Tim is set to return to Earth on 18 June 2016, bringing his six-month Principia mission to the ISS to an end. During his stay he performed more than 30 scientific experiments for ESA and taking part in numerous others from ESA's international partners. ESA and the UK Space Agency have partnered to develop many exciting educational activities around the Principia mission, aimed at sparking the interest of young children in science and space. (Photo by Tim Peake/ESA/NASA)

People look at a 1939 Alfa Romeo 8C 2900B Lungo Touring Spider displayed at Sotheby's in New York City, New York, U.S. July 21, 2016. The car, unveiled in a pre-publicity showing in New York on Thursday, is expected to sell for more than US$15 million – and could set a record for the most money ever paid for a pre-war auto at auction. (Photo by Brendan McDermid/Reuters)

MTV's “Ex On The Beach” star Jemma Lucy gives her neighbours an eyeful as she takes her bins out in her underwear in Manchester, UK on August 22, 2016. Jemma Lucy is well known in UK for her love of flashing more than a little bit of flesh on a night out. But the reality star took things a step further this week as she took out the bins wearing nothing but her bra and knickers. (Photo by XposurePhotos.com)

Under Exposed: Pekka Tuuri (Finland) – Great white shark, Isla Guadalupe, Mexico. “Isla Guadalupe is the world capital when it comes to observing great white sharks, but cage diving seriously limits the possibilities to take ‘fresh’ pictures. When I took this, the water close to the surface was quite milky, making photography very challenging. From out of the “mist”, I saw this great white shark lurking behind a school of fusiliers. I quickly focused on the shark and set a wide aperture to get focus blur on the fish, along with a fast shutter to avoid excessive motion blur”. (Photo by Pekka Tuuri/The Outdoor Photographer of the Year/The Guardian)

This graceful husky appears to be smarter than your average dog having apparently mastered the art of walking on water. The soft-footed canine was photographed while making its way across a lake in northern Russia. Photographer Fox Grom captured a remarkable set of images after heavy rain fell on a frozen lake to create the amazing illusion. The 40-year-old, who works as an all-terrain vehicle driver, regularly walks his pet dogs, Alaska and Blizzard, near the natural beauty spot. “I always take pictures of my dogs whilst walking them but on this occasion there was an extraordinary phenomenon“, he said. “The ice was already very thick when it rained heavily making for a spectacular scene”. Here: Husky dog Alaska walks on water in Northern Russia, January 2015. (Photo by Fox Grom/Visual Press Agency)