People visiting the observation centrepiece of the 1,250m-long Tree Top path in Prora, Germany, last Sunday.
In 2013, the Naturerbe Zentrum, or heritage centre, opened with the tree observation tower in the shape of an eagle eyrie on the beech forest on the island of Rugen.
An eyrie is a nest that is built high up among rocks by a bird of prey.
Sited in the eastern part of Rugen, the centre covers 1,900ha and is home to three different habitat types: forest, open habitats and wetlands. Previously a restricted military area, the grounds are now home to numerous plant and animal species, including giant beeches that are more than 100 years old.
The Tree Top Walk takes visitors through the forest canopy and is packed with information and adventure stations.
The eyrie viewing platform, 40m above the ground, gives a bird's eye view of the island, the Kleiner Jasmunder lagoon and the Baltic Sea.
About 700,000 people have visited the site in the last two years.