Madeira Caldeirão do Inferno", which should not be attempted by hikers prone to vertigo or without torches and helmets. The "Levada do Caniçal" is a much easier walk, running from Maroços to the "Caniçal Tunnel". It is known as the "mimosa levada", because "mimosa" trees, (the colloquial name for invasive acacia) are found all along the route. Administratively, Madeira (with a population of 267,302 inhabitants in 2011) and covering an area of is organised into eleven municipalities: Funchal is the capital and principal city of the Autonomous Region of Madeira, located along the southern coast of the island of Madeira. It
Madeira over 6,000 "arrobas" (an "arroba" was equal to 11 to 12 kilograms) by 1455, using advisers from Sicily and financed by Genoese capital. (Genoa acted as an integral part of the island economy until the 17th century.) The accessibility of Madeira attracted Genoese and Flemish traders, who were keen to bypass Venetian monopolies. Sugarcane production was the primary engine of the island's economy, increasing the demand for labour. African slaves were used during portions of the island's history to cultivate sugar cane, and the proportion of imported slaves reached 10% of the total population of Madeira by the 16th century.