Ngorongoro Crater (Tanzania). At 610m deep and 260 sq km, this is the largest unflooded caldera in the world. A blue-green vision from above it's a haven for engangered wildlife and Maasai livestock. The crater was formed three million years ago when a giant volcano, which could have been as high as Kilimanjaro, exploded and collapsed. The caldera formed the concentric fractures in the crust cracked down to a magma reservoir deep underground. (Photo by John Bryant/Getty Images)

A Sri Lankan activist, who wrapped himself with fire crackers, walks in Colombo on July 23, 2014 to symbolically demonstrate against people burned during Anti-Tamil riots on the island thirty-one years ago. Official accounts placed the death toll at 400 while human rights activists put the toll at thousands. (Photo by Ishara S.Kodikara/AFP Photo)

The Schimmel Pegasus Grand Piano looks more like a spaceship or something else from the Sci-Fi channel than a piano. Schimmel made 14 of these about 10 years ago for people like Prince, Eddie Murphy and Lenny Kravitz. If you have tonnes of money, there is currently one for sale. They are asking US$110,000.

Ratko Mladic makes his first appearance at the International Criminal Tribunal on June 3, 2011 in The Hague, Netherlands. Ex-Bosnian Serb army leader Ratko Mladic will make his first appearance at The Hague war crimes tribunal after being declared fit to stand trial. Mladic was arrested a week ago after going into hiding for the past 16 years and is charged with atrocities committed during the Bosnian war. (Photo Serge Ligtenberg/Getty Images )

Israelis participate in a “Zombie Walk” during the Jewish holiday of Purim on March 6, 2012 in Tel Aviv, Israel. The carnival-like Purim holiday is celebrated with parades and costume parties to commemorate the deliverance of the Jewish people from a plot to exterminate them in the ancient Persian empire 2,500 years ago, as described in the Book of Esther. (Photo by Uriel Sinai/Getty Images)

This particular Gingko tree (aka Gingko Biloba) is not just any tree. It was reportedly planted by Tang Dynasty's Emperor Taizong, the emperor portrayed in Fang Bingbing's Empress of China, from over a thousand years ago. Take a look at these stunning photos when the Gingko tree displays its full glory in late autumn.

Natsumi Hayashi is a Japanese artist known for her fixation with levitating. Two years, ago, the photographer began posting portraits online of herself floating in mid-air. The magical project – titled “Today's Levitation” – is the subject of a playful survey of her year-long obsession with flying.

A year ago, we at HootSuite showed just how much we love Game of Thrones with our Social Media Winter is Coming infographic. The infographic was a visual representation of the quiet battles being fought between many social networks, who were building walls and blocking access between their respective sites and apps. That graphic was a hit with the social media community, so we knew we had to take things up a notch for this season’s premiere. Enter the Game of Social Thrones video.