Giant's Causeway cases the horizontal fracture has resulted in a bottom face that is convex while the upper face of the lower segment is concave, producing what are called "ball and socket" joints. The size of the columns is primarily determined by the speed at which lava from a volcanic eruption cools. The extensive fracture network produced the distinctive columns seen today. The basalts were originally part of a great volcanic plateau called the Thulean Plateau which formed during the Paleocene. According to legend, the columns are the remains of a causeway built by a giant. The story goes that the Irish
François Leguat Giant Tortoise and Cave Reserve yet rehabilitated. The reserve's tours include a trip through the caves, which are the only caves in the Indian ocean equipped with lights. Francois Leguat Reserve is located on the Anse Quitor peninsula in the south-west of the island, a few hundred meters from the Rodrigues airport and right beside Anse Quitor Nature Reserve (not yet open to the public). François Leguat Giant Tortoise and Cave Reserve François Leguat Giant Tortoise and Cave Reserve ("Francois Leguat Reserve") is a park and nature reserve on the island of Rodrigues, dedicated to protecting the fauna and flora of the island. The reserve