Iceland is the world's largest volcanic island, a fact that's makes it a breathtaking, but deadly, geological marvel. Take a journey along a ridge that divides continents, follow endless fields of solidified lava, and witness the rare and striking spectacle of a volcano erupting under a glacier.

Eleven percent of Iceland remains covered by glaciers. And although these titanic ice sheets recede every year, their tremendous power continues to change the landscape. Witness how the glaciers carve out fjords, valleys, and mountains, and lead to some of the world's most spectacular waterfalls.

Mosses that tower 10 stories high and insects of horror-film proportions are part of the Bay of Fundy's peculiar ecosystem, which dates back hundreds of millions of years. With the highest tides on Earth, waves rip rocks off cliffs and reveal fossils that are vital to understanding the history of our planet.

The hostile waters surrounding Wales have caused hundreds of shipwrecks and sculpted the stunning scenery of its wild coastline. Take a serene tour of the world's longest continuous coastal footpath and explore its mysterious caves, cliffs full of fossils, and causeways that disappear.

Ireland is a land studded with majestic natural landmarks. Learn the history and myths behind the distinctive features of this rugged island, including the 700-foot-tall Cliffs of Moher, the 40,000 stone columns known as Giant's Causeway, and Slieve Gullion, a mountain that rose from molten rock.

The tectonic forces that bring life to Canada's rainforest paradise, Vancouver Island, belie a dangerous feature: the inevitability of a megathrust earthquake that could trigger a 4,000-mile tsunami! The question scientists have yet to answer is when it will strike.