German firm Baumraum is specialized in planning and developing tree houses, either built on the ground (at a dizzy height) or on water. Froschkönig (German for Frog King) is a project that left us speechless. Located in a private garden in Munster, the delightful playground was built on four steel columns. The interior looks great due to the curved glass surface, gable roof and light flooding the elongated windows. You could say that the most attractive part of the luxurious play room is a large “ceiling” window, allowing children to look up in the sky and observe the stars at night. What a way to learn the constellations! The tree house features enough storage space for books, games or blankets. A large deck area makes for the perfect playing spot. Check out the company’s website for more stunning tree houses and even tree hotels!