![Hardy adventurers raft on a river nicknamed the \](http://www.ecns.cn/hd/2018/12/14/3e77c8dd708e47298f51d2fe8a5670e3.jpg)
Hardy adventurers raft on a river nicknamed the "unfrozen river” with the banks covered in snow in Arxan City, North China’s Inner Mongolia Autonomous Region, Dec. 13, 2018. The 20-kilometer-long river section, 74 kilometers from downtown, never freezes even in the coldest winter due to geothermy. (Photo: China News Service/Zhong Xin)
![Hardy adventurers raft on a river nicknamed the \](http://www.ecns.cn/hd/2018/12/14/09cd6213b7c14051be05c989736f1c82.jpg)
Hardy adventurers raft on a river nicknamed the "unfrozen river” with the banks covered in snow in Arxan City, North China’s Inner Mongolia Autonomous Region, Dec. 13, 2018. The 20-kilometer-long river section, 74 kilometers from downtown, never freezes even in the coldest winter due to geothermy. (Photo: China News Service/Zhong Xin)
![Hardy adventurers raft on a river nicknamed the \](http://www.ecns.cn/hd/2018/12/14/8a1e981fa8864eeb9e7120478c4d3ce8.jpg)
Hardy adventurers raft on a river nicknamed the "unfrozen river” with the banks covered in snow in Arxan City, North China’s Inner Mongolia Autonomous Region, Dec. 13, 2018. The 20-kilometer-long river section, 74 kilometers from downtown, never freezes even in the coldest winter due to geothermy. (Photo: China News Service/Zhong Xin)
![Hardy adventurers raft on a river nicknamed the ‘unfrozen river” with the banks covered in snow in Arxan City, North China’s Inner Mongolia Autonomous Region, Dec. 13, 2018. The 20-kilometer-long river section, 74 kilometers from downtown, never freezes even in the coldest winter due to geothermy. (Photo: China News Service/Zhong Xin)](http://www.ecns.cn/hd/2018/12/14/0c086107874a44bfab13d1007ae56f46.jpg)
Hardy adventurers raft on a river nicknamed the ‘unfrozen river” with the banks covered in snow in Arxan City, North China’s Inner Mongolia Autonomous Region, Dec. 13, 2018. The 20-kilometer-long river section, 74 kilometers from downtown, never freezes even in the coldest winter due to geothermy. (Photo: China News Service/Zhong Xin)