The day I got a free car

The only plausable way I can see a lush oasis like enviroment existing in the region of the north pole is if:
There is a huge underground cavern and cave system warmed and lighted by geothermal vents and underground volcanoes, as to how animals/humans or plants like trees could get there, while I really dont know

Just stumbled on this link:
www.abovetopsecret.com...

Maybe my co-workers have planned this out.