There are no sign plates warning against touching in the first German museum dedicated to mathematics. On the contrary, visitors can touch over a hundred interactive exhibits here. There is a special department – Minimatematikum- for the youngest. In that depratment numbers, shapes, geometric figures are told about intelligibly. More complicated exhibits await older visitors: they are offered to resolve puzzles, fit together math puzzles, to learn in practice what the golden section is and even construct a bridge designed by Leonardo da Vinci!