The dramatic moment a tree tumbled down a cliff towards walkers during a landslide was caught on camera. Footage of the incident - the third landslide in the last month - is worrying local residents.

The video shows an area in Antarctica where rocky outcroppings jut up above the ice sheet. The building is a South African research station.

For an annual fee of $100 -- or $125 for a two-person membership and $175 for a family -- you can enjoy the rush of climbing up the tree-lined quarry walls, only to plummet from a one-story cliff ...