Experts still divided over mysterious 1,300-year-old fortress-like structure located on island in middle of lake.

Gas bubbles from waters filling crater hole on Yamal peninsula two months after volcanic-style explosion in thawing permafrost.

Pipes are built over bulging and unstable Arctic pingos prone to violent eruptions caused by 'thawing methane gas', as seen twice on the Yamal peninsula this year.

Angelina Sadovnikova, then 11, came across the mummified Pleistocene rodent in a cavity left by woolly mammoth tusk diggers.

Valuable obsidian travelled during Early Holocene times from Lake  Krasnoe in Chukotka to Zhokhov Island deep in the Arctic.

Eyecatching belt buckles worn by Xiongnu female invaders is found buried on the banks of the Yenesei River in modern-day Tuva Republic.