The Mauritius Island (Mauritian Creole: ''Isle Moris''; , ) is relatively young geologically, having been created by volcanic activity some 8 million years ago. Together with Saint Brandon, Réunion, and Rodrigues, the island is part of the Mascarene Islands. These islands emerged as a result of gigantic underwater volcanic eruptions that happened thousands of kilometres to the east of the continental block made up of Africa and Madagascar. They are no longer volcanically active and the hotspot now rests under Réunion Island. Mauritius is encircled by a broken ring of mountain ranges, varying in height from  above sea level. The land rises from coastal plains to a central plateau where it reaches a height of ; the highest peak is in the south-west, Piton de la Petite Rivière Noire at . Streams and rivers speckle the island, many formed in the cracks created by lava flows.