Trekking

First established as a national park in 1934 Iguazu national park is probably the most stunning of all of Argentina's parks. A haven for the eco-tourist this park is home to many beautiful sites and a range of stunning landscape, the most notable of which is the world famous Iguazu waterfalls.

Located on the border between Argentina and Brazil, the Iguazu waterfall is something to behold. At 80 meters high and with a diameter of nearly 3km the only way to really appreciate the waterfalls are to see them in the flesh.

Inga Falls is a rapids in the Democratic Republic of the Congo, where the Congo River drops a staggering 96m (315 ft) over a 15 km (9mi) course. The rapids are extremely lively - the Inga Falls actually form part of a larger group of rapids known as the Livingstone Falls - and have formed a sharp bend in the river, the width of which fluctuates from a mere 260m to an enormous 4 km.

There is much more to Lapland than just visiting Santa as any eco tourist who has visited Abisko National Park will tell you. Established just over 100 years ago Abisko is Sweden's most famous national park and covers an area of around 77sq km.

The Moeraki Boulders are the huge and phenomenally spherical boulders like giant cannon balls found on Koekohe Beach on the coast of New Zealand. They are specially protected as part of a scientific reserve to ensure their lasting beauty and scientific interest. They range in size from about 0.5 to 1 metres (1.6 to 3.3 ft) in diameter, to well over 2 metres (7 ft).

Derweze is an isolated village in Turkmenistan with a very sparse population of just 350 inhabitants located in the middle of the Karakum Desert. The Derweze Area is rich in natural gas. Whilst drilling in 1971, geologists tapped into a cavern filled with this gas, and the ground beneath the drilling rig collapsed, leaving a huge gaping wound in the Earth's very crust about 70m (230ft) in diameter.