This Arctic field, located on a peninsula jutting out into the Kara Sea, is estimated to hold 173 trillion cubic feet of gas -- twice what's thought to be in the United States' Marcellus Shale.
Infrastructure is always a challenge in a remote region. Gazprom had to build a 355-mile railroad to haul in construction supplies, and an even longer pipeline to get the gas out. The gas will be fed into Russia's vast pipeline system.
