What looks like a post-apocalyptic garden is actually a memorial site created in 1990 by environmental artist Ben Wagin atop a section of the Berlin Wall. The installation centres on 16 trees, each representing a German state (hence the name), which are surrounded by 58 original pieces of the Wall listing the names of 258 people who died trying to escape to the West.
It's a poignant and contemplative place, further enhanced by pictures, text and memorial stones.