For more than 25 years, there has been a public observatory in the former customs house at the border checkpoint. This observatory is still largely run by amateur astronomy enthusiasts. They created this observatory piece by piece, building an auditorium, a library, a gallery and a workshop to build your own telescope. In 2005, the members built a 61 centimetre Cassegrain telescope as a prototype optimised for visual observation and which is now the largest and most powerful telescope is Berlin. Regular public sky observations, workshops, lectures on astronomy topics and excursions are offered.