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.

A shoebill is displayed at Ueno Zoo in Tokyo August 28, 2012. (Photo by Itsuo Inouye/Associated Press)

Archie McQuater, 82-year-old clockmaker at Craiglea clocks, adjusts a clock face to British Summer Time (BST) on March 25, 2011 in Edinburgh, Scotland. Clocks will be put forward by one hour at 1:00 AM GMT on Sunday March 27, 2011 officially the start of British Summer Time. British Summer Time will end this year on October 30. (Photo by Jeff J Mitchell/Getty Images)

A model showcases designs by Antonia Paris during the Women's RTW 3 catwalk during Rosemount Australian Fashion Week Spring/Summer 2011/12 at Overseas Passenger Terminal on May 5, 2011 in Sydney, Australia. (Photo by Stefan Gosatti/Getty Images)

A model showcases designs by Isola by Megan Gale on the catwalk at the David Jones Spring/Summer 2011 season launch at the Royal Hall of Industries, Moore Park on August 3, 2011 in Sydney, Australia. (Photo by Lisa Maree Williams/Getty Images)

In this handout image provided by Sydney Tower Eye, a visitor scans the skyline and harbour of Sydney from a viewing platform at the Sydney Tower Eye, on December 16, 2011 in Sydney, Australia. Sydney is suffering from its coldest start to summer since 1960. (Photo by Eugene Tan/Hausmann Communications via Getty Images)

Alan Wilson, Director of James Ritchie & Son clockmakers, founded in 1809, adjusts a clock face at the Cannongate Tobooth to British Summer Time on March 21, 2012 in Edinburgh, Scotland. The Tolbooth, built in 1591, was where tolls and public dues were collected. The clock face dates back to 1820 and replaced an earlier clock from the 17th Century. Clocks will be put forward by one hour on Sunday March 25, 2012 at 1.00am and British Summer Time (BST) will officially start. (Photo by Jeff J. Mitchell/Getty Images)

Children fall as they slide down on a float along a chute to cross a pool of water and foam during the “Letniy Gornoluzhnik” (Summer mountain puddle rider) festival at the Bobroviy Log Fun Park near the Siberian city of Krasnoyarsk, Russia, August 23, 2015. The annual competition marks the end of the summer season at the Siberian ski, rest and entertainment resort. (Photo by Ilya Naymushin/Reuters)