The Laurel forest, also called laurisilva or laurissilva, is a type of subtropical forest found in areas with high humidity and relatively stable, mild temperatures. The forest is characterized by broadleaf tree species with evergreen, glossy and elongated leaves, known as "laurophyll" or "lauroid". Plants from the laurel family (Lauraceae) are also present at the Madeira´s Laurissilva forest which is a UNESCO heritage site. It is a rare and fragile ecosystem. The paleobotanical record of Madeira reveals that laurissilva forests has existed in this island for at least 1.8 million years. The levada 25 fontes was built in the late 18 th century, and transports water from Rabaçal to the south of the island. Rabaçal can be described as valley of vertical walls where different types of volcanic rock allow water from the upper water table to emerge in the form of numerous fountains along the walls of the mountain.