Canyons (ocasionally known cañon or gorge) are true unsual natural wonders. Seen from above, they are impressive, but walk down into a canyon to discover the true hidden world. Some are carved by rivers, above ground, exposing cliffs of sandstone or granite, some, the "submarine canyons" are underwater, at the mouth of rivers. Some are built through a geological or tectonical uplifts and some are rifts between moutains, carving the landscape deep, creating fairytale like scenes.
Are you looking for the ultimate adventure? What could be more exciting, thrilling and adventurous than climbing an active volcano? Kilauea Volcano, on Hawaii's Big Island, has been erupting non-stop since January 3, 1983 and Stromboli Volcano in Italy is erupting nearly continuously for over 2,000 years!