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.

This Sunday, September 7, 2014 photo provided by Rachel Kirk shows smoke from a fire rising above Little Yosemite Valley near Yosemite National Park, Calif. (Photo by Rachel Kirk/AP Photo)

Every year National Parks Week gives visitors a chance to celebrate the incredible woodland spaces around the UK. This year the National Parks Week runs from 28 July – 3 August and there are 10 national parks across England to explore. Each one has created a special event to celebrate the National Parks Week, from picnics and treasure hunt in the park to cycle rides, safari or outdoor art exhibition. (Photo by Diana Jarvis/VisitEngland)

The delegates arrive at the Great Hall of the People before a plenary session of the National People's Congress on March 11, 2011 in Beijing, China. The NPC will take place until March 14. (Photo by Feng Li/Getty Images)

Merfolk gather at MerMania 2017, the world's largest gathering of amateur and professional mermaids and mermen in North Carloina, USA on January 21, 2017. (Photo by Brian Cahn/ZUMA Wire/Rex Features/Shutterstock)

A so-called “Supermoon” dominates the sky while traffic rolls in the streets in Naypyitaw, Myanmar, 03 December 2017. According to the National Aeronautics and Space Administration (NASA) a series of three “Supermoons” – dubbed the “Supermoon trilogy” – will appear in the sky on 03 December 2017, on 01 January 2018 and and 31 January 2018. A “Supermoon” commonly is a full moon at its closest distance to the earth with the moon appearing larger than usual. (Photo by Hein Htet/EPA/EFE)

Blue, white and red brassieres, the colours of the French national flag, hang from a balcony in Marseille, France, November 27, 2015 as the French President called on all French citizens to hang the tricolour national flag from their windows on Friday to pay tribute to the victims of the Paris attacks during a national day of homage. (Photo by Jean-Paul Pelissier/Reuters)

Bao Bao the panda, one of the National Zoological Park’s cutest inhabitants in Washington, D.C., recently celebrated her first birthday on August 23rd. As part of the celebration, Bao Bao got her very own cake. The large tiered cake showcased a big number 1.