A wolf looks into the camera at the 30 km (19 miles) exclusion zone around the Chernobyl nuclear reactor in the abandoned village of Orevichi, Belarus, March 2, 2016. What happens to the environment when humans disappear? Thirty years after the Chernobyl nuclear disaster, booming populations of wolf, elk and other wildlife in the vast contaminated zone in Belarus and Ukraine provide a clue. (Photo by Vasily Fedosenko/Reuters)

Londoners sleep on the platform and on the train tracks at Aldwych Underground station,London, during heavy all night Nazi bombing raids, October 8, 1940. (Photo by AP Photo)

Last weekend, the National Building Museum in Washington, D.C., opened a 10,000 square-foot ball pit to the general public, and everyone cheered that, finally, someone made their childhood dreams come true.

English fashion modelDaisy Lowe performs a DJ set for Badoos #DateOfTheDead party at La Bodega Negra on October 26, 2017 in London, England. (Photo by Tabatha Fireman/Tabatha Fireman/Getty Images for Badoo)

Trees are reflected on the surface of a lake in the Okefenokee swamp lands in Georgia, USA on October 21, 2017. (Photo by Chris Moore/Solent News & Photo Agency)

The HFR x LeBron 16 shoe is unveiled at the Harlem Fashion Row show and awards ceremony before the start of New York Fashion Week, Tuesday, September 4, 2018. (Photo by Diane Bondareff/AP Photo)

Zozibini Tunzi, of South Africa, is crowned Miss Universe by her predecessor, Catriona Gray of the Philippines, at the 2019 Miss Universe pageant at Tyler Perry Studios in Atlanta, Georgia, U.S. December 8, 2019. (Photo by Elijah Nouvelage/Reuters)

This picture taken on December 15, 2019 shows three young orangutans after they were rescued by police from illegal wildlife traffickers in Pekanbaru in Riau province, Indonesia. (Photo by Wahyudi/Jefta Images/Barcroft Media)