A renaissance of one of Siberia's first outposts as the Far North becomes the new economic frontier.
Satellites show giant hole ringed by 20 'baby craters'.
Local reindeer herder witnessed the tundra explosion that led to birth of new hole in river.
Mysterious 'gigantic' hole in remote region spotted by helicopters over gas-rich Yamal peninsula.
Reindeer herders find more craters in the far north in a deepening puzzle for scientists.
Scientists rush to site of latest tundra eruption - which formed a crater 50 metres deep - amid fears for homes and key industrial sites.
New road and rail link over the Nadym River.