Son doong cave is a cave in Phong Nha-Kẻ Bàng National Park, Bố Trạch district, Quảng Bình Province, Vietnam. Currently the biggest known cave in the world, the cave is located near the Laos-Vietnam border. Inside is a large, fast-flowing underground river.
In early August 2013, the first tourist group explored the cave on a guided tour at a cost of US$3,000 each. The group had six members from Australia, Norway, Russia and USA and spent 7 days and 6 nights for the tour. Next exploration trips will be arranged.

The Wovel could possibly be the most advanced human snow removal machine ever created, next to simply getting someone else to do it. The revolutionary wheel design reduces the risks associated with heart attacks and back injuries because it uses adjustable leverage and your own body weight to push, lift, and throw snow up to 18" deep. The best feature about the Wovel is compared to a gas-powered snow blower, this one will always start.

“In 1967, Zhang Yaxin was 34 and working as a photojournalist at China’s state-controlled Xinhua News Agency when he was assigned to a top-secret government project. He was to be the official photographer of a new arts program led by Chairman Mao and his wife – the Model Operas. Though he was not to know it then, Zhang would spend the next seven years documenting the evolution of one of the most dramatic and elaborate attempts to redefine artistic sensibilities in modern art history”. – Chengcheng Jiang via TIME. Photo: Raid on the White Tiger Regiment, 1971. (Photo by Zhang Yaxin/Courtesy See+ Gallery, Beijing)

This undated handout picture made available on February 3, 2016 and provided by Russia's punk band Рussy Riot shows Рussy Riot frontwoman Nadezhda Tolokonnikova performing in the band's new music video titled “Chaika” in Moscow. Russian punk band Рussy Riot, which became a symbol of resistance for a church performance slamming President Vladimir Putin, released a new protest song on February 3 mocking a senior official for alleged corruption. Titled “Chaika”, the satirical song and accompanying video take aim at prosecutor general Yury Chaika, whose two sons have been accused of using their father's position to accrue large fortunes. (Photo by Andrey Noskov/AFP Photo/Russian Punk Band Рussy Riot)

Camp dwellers pump water from a well at Malkohi refugee camp in Jimeta, Adamawa State, Nigeria on February 19, 2019, four days ahead of the country's General elections set for February 23 after a last-minute rescheduling. Malkohi is a camp for internal displaced who fled their homes as Boko Haram insurgents advanced across north-eastern Nigeria. From their homes on the outskirts of Yola, capital of presidential candidate Atiku Abubakar's home state Adamawa, Malkohi residents say they feel forgotten. (Photo by Luis Tato/AFP Photo)

Members of a samba school warm up before parading along Copacabana Beach in Rio de Janeiro, Brazil, Saturday, January 6, 2018. Musicians and members from Rio de Janeiro's top 13 samba schools have paraded in an event aimed at promoting tourism ahead of Rio's world famous Carnival that begins early next month. (Photo by Leo Correa/AP Photo)

A Santa Claus taking a selfie on a surfboard is seen in the yard of a home in the Sleepy Hollow area of Torrance, California, United States, December 15, 2015. In many neighborhoods of Los Angeles, homeowners compete for the most lavish and creative holiday light displays. Torrance's Sleepy Hollow is one such neighborhood where every home outdoes the next: surfing Santas, life-size nativity scenes, ferris wheels, and giant inflatable snowmen line the lawns on every street. (Photo by Lucy Nicholson/Reuters)