A visitor walks inside the initiation well at Quinta da Regaleira in Sintra October 6, 2014. Sintra became the first centre of European Romantic architecture in the 19th century, which influenced the development of landscape architecture throughout Europe. It was classified as a World Heritage Site by UNESCO in 1995. Its monuments are visited by more than 1.5 million of tourists every year, according to local media. (Photo by Rafael Marchante/Reuters)

Participants climb over a wall at the “Tough Mudder” endurance event series in Arnsberg September 6, 2014. Competitors who took part in the endurance event saw themselves having to overcome various military style obstacles. (Photo by Ina Fassbender/Reuters)

Rita Ora strips down to promote the new Tezenis lingerie range on December 7, 2016. The British singer, 26, shows off her curves in the latest campaign for the Italian brand. (Photo by Splash News/Tezenis)

Migrants rush as they try to get on a train heading to the border with Serbia at the train station of Gevgelija, on the Macedonian-Greek border, on August 9, 2015. Non-EU Serbia's frontier with Hungary, which is in the bloc's passport-free Schengen zone, has become a major crossing point for the huge numbers of migrants entering the EU. (Photo by Dimitar Dilkoff/AFP Photo)

A Ukrainian police officer takes cover in front of a burning building that was hit in a Russian airstrike in Avdiivka, Ukraine, Friday, March 17, 2023. (Photo by Evgeniy Maloletka/AP Photo)

With the help of some fake teeth and multiple exposures, New York AP photographer Eddie Adams' daughter Susan is transformed into a little ghoul on Halloween night, October 31, 1966. (Photo by Eddie Adams/AP Photo)

A tourist is seen at the Caka Salt Lake in Wulan County, northwest China's Qinghai Province, September 4, 2020. (Photo by Zhang Long/Xinhua News Agency)