Geography and Geology of Mauritius

Formation of Mauritius

Mauritius is a tiny, seemingly insignificant island 890km east of Madagascar and 1200km off the coast of Africa. It was created by volcanic activity eight million years ago. The volcanic peak has been eroded and shaped the dramatic mountains and rock formations found on Mauritius today.

From high above the ground these fragmented lava-rock peaks form an irregular circle, but within the remnants of this older activity lie a series of younger smaller craters including Grand Bassin and Trou aux Cerfs, indicating that Mauritius volcano rumbled back to life again after a lull of over 2 million years.

The northern islands – Coin de Mire and Ile aux Serpents – are also the remnants of younger volcanoes that were still active at the time of the last ice age. These became separate from the mainland when the sea level rose as the ice shields retreated.

Volcanic activity on Mauritius has ceased.

Mauritius Today

Mauritius is 61 km long and 46 km wide at its extremes. It and its two smaller siblings constitute the Mascarene Islands. All three sit on a shallow submarine ridge that arcs northeast from the African coast. Rodrigues, 600km northwest, is part of the greater state of Mauritius, while Réunion, only 200km to the southwest is now French sovereign territory.

Since independence Mauritius also holds sway over the tiny unpopulated islands of Agalega and the Cargados Shoals and has lodges disputes with France over its territorial claims of Tromelin and with Great Britain over the Chagos Archipelago. Mauritian sea territory is vast in comparison with its landmass, at 1.2 million square kilometres.

Mauritius island geography is complicated for such a small landmass. Lowland plains cover over 40 percent of the island and today much of this is exclusively devoted to sugar-cane cultivation with some vegetables grown for the domestic market. Though fertile, this land was strewn with large fragments of tuff and lava stone forced from the volcano. These rocks are a constant problem for mechanization of agriculture in Mauritius.

From the lowlands the terrain climbs inland to a central plateau that constitutes around 25 percent of total area. The plateau is home to most of the 1.2 million inhabitants of Mauritius.

Mountains make up just under 20 percent of the island area. It is not the height – between 600 and 800km – but the dramatic outline of these mountain peaks that make them so memorable. The Long Mountain to Anse Courtois range wrapping around the capital gives Port Louis the most dramatic of settings. The highest and most remarkable peak of this chain is the Pieter Both (823km), because it has a loose rock at the summit sitting like a head on shoulders.

View our Map of Mauritius