Alexandr Orlov
Google
Amazing European collection of mathematical and physical Instruments.
Considering my tastes and interests, I think it was the most interesting museum for me that I have ever visited. This is a huge collection of everything related to accurate calculations of the past: mathematical and physical devices and instruments, geographical and astronomical devises and instruments. All kinds of watches and compasses, computing devices and so on. It was an unforgettable experience in its own way and I highly recommend visiting it for those who are also interested in such things... and just advising it to visit to those who came to Zwinger (like its other museums, such as art and porcelain collections).