Defined by its volcanic formation, Reunion Island is home to two shield volcanoes, Piton de la Fournaise and Piton des Neiges, the latter also being responsible for the forming of the three volcanic calderas. It is thus fair to say that these volcanoes shaped the landscape and lifestyle of the island's inhabitants.

Measuring an impressive 3,070 metres, its peak constituting the highest point on entire island and also in the Indian Ocean, Piton des Neiges is now inactive and has been so for twenty thousand years. It is positioned in the north-west of the island and is surrounded by the Cirques, forming sceneries of outstanding beauty. Although its name is highly suggestive, Snowy Peak, there is hardly ever any snow there, except at extremely high altitudes and not in significant quantities. There are many hiking paths one can set off on, assessed according to the challenge they pose. Moreover, for those seeking more information about the local flora and fauna, a visit to the national reserve situated at the foot of the mountain is warmly recommended. In terms of tourism, evaluations place Piton des Neiges as a definite winner on the list of visitors' preferences.

Unlike Piton des Neiges, which is inactive and eroded, Piton de la Fournaise is still highly active – as a matter of fact it is counted among the most active volcanoes on the globe. Piton de la Fournaise is 2,631 metres high and due to its very intense activity (180 eruptions since the 17th century) it is being closely watched in order to anticipate any future eruptions as well as their magnitude. Helicopter tours are available for those who want a perspective from a different angle; in fact they are quite common. Many tourists venture on foot to the highest reachable points on the mountain, which is described as an unforgettable sight.