The Hollow Oak of Jenischpark

Hamburg's thickest oak has a hole in it big enough to stand in. The opening runs up one side of the trunk from just above the ground to more than four metres, and the tree simply carries on around it: 8.30 metres of girth when it was last taped in April 2020, agreed to the centimetre by two separate German tree registers, and wider than any other pedunculate oak in the city. Nobody recorded the planting. German arboriculture dates a tree like this from its trunk instead, which puts it at about 1600 with fifty years of tolerance either way, so somewhere between 375 and 475 years old. Either end of that band leaves it standing here long before the ground around it became a park. Jenischpark was laid out as an English landscape garden above the Elbe in the early 1800s, and the oak was already a large tree when that work began. It has had help staying upright. In 1972 the tree surgeon Michael Maurer restored the trunk and braced the opening with iron rods, which are still in place and visible from several metres away. The park is free, open and ungated, and the oak stands about 100 metres east of the Jenischhaus, the villa that gives the place its name.