In the early 15th century, Portuguese settlers found an uninhabited, densely forested, mountainous island, which they named Ilha de Madeira, meaning 'Island of wood'. After clearing the mountain slopes for cultivation, they realized that although the north of the island had more water than it needed, the south - the best agricultural land - was dry for much of the year.
This led to the building of levadas, a huge system of irrigation channels that divert the excess water from the mountains to the rest of the island. Many were dug into the ground, but many others were hand-hewn into rock or tunnelled through mountains, often by slave labour from Portugal's colonial empire. Today the 2000 km (l250 mi) long system is still being expanded, and the footpaths alongside the levadas, essential for maintenance, are now a favourite destination for walkers, and a perfect way of exploring the stunning interior of the island.
The levada of Caldeirao Verde, (Green Cauldron) built in the 18th century, is a beautiful, steep walk, begirming at Queimadas Forestry Park, at an altitude of 890 m (2900 ft). The path first takes you up through the forest of laurels, beeches, Japanese cedars and junipers, soon providing spectacular views of the terracotta roof tiles of the villages below. The route winds through four different tunnels, the second of which is 200 m (660 ft) long, each carved by hand, after which you will soon see the Caldeirao on your left - a natural, mossy rock bowl containing a waterfall-fed lake. All along the narrow path, moss, ferns and lichen growing to either side, you will see dramatic mountain scenery, and by the time you reach the Caldeirao you'll be glad to have a rest and, perhaps, a picnic, with just the sounds of splashing water and birdsong for company.
WHEN TO GO
April to November
TIME IT TAKES
Two to three hours
Levada of 25 Fontes - where you will find 25 springs cascading into a lake.
Ribeiro Frio to Portela. through glorious heather forests.
The UNESCO World Heritage Nature Site (1999) of Madeira's Laurissilva Forest.
The volcanic caves of Sao Vicente.
YOU SHOULD KNOW
Some levada walks are much harder than others. For this one, take walking boots and a torch for the tunnels.