Apart from the historic buildings, the centerpiece of Mainau Island is the Arboretum with its 500 different types of rare and valuable broad-leaved trees and conifers, which was created in 1856 by grand duke Friedrich I. Among those is one of Germany's "oldest" dawn redwood trees (Metasequoia glyptostroboides). The tree, which originated from China, was planted on the island in 1952, when it was just 70 centimeters tall. Particularly mighty are some exemplars of the giant redwood (Sequoiadendron giganteum). Their seeds came from California in 1853 and were planted on the island in 1864, which makes them one of the oldest of their kind in Europe. You can find the above-mentioned giant redwoods as well as Cedars, Dawn Redwoods and Tulip Poplars on the island. The Arboretum expands towards the north-west of the island.