Follow in the footsteps of Heinz Sielmann in Duderstadt. The Heinz Sielmann Foundation is located in Herbigshagen near Duderstadt. Here you can experience nature with all your senses. With sleeperoo the nature experience becomes perfect. Next to a meadow of flowers is a cozy Design|sleep Cube. Here you spend the night alone. The stars twinkle above you, it rustles in the grass, it smells like nature… what an experience.