The Geological Museum on Vasilievsky Island is run by and located inside the Aleksandr Karpinsky All-Russian Scientific and Research Geological Institute.  The institute is known by its Russian initialism of VSEGEY (which rather amusingly spells out 'everybody is gay' in Russian). The museum consists of one giant hall filled with thousands of examples of rocks, as well as the odd fossil and dinosaur skeleton. Its main attraction though is the large map of the Soviet Union which is made out of the minerals found in each part of the country. Although its subject might not appeal to everybody it nevertheless has a lot of charm and some of the rocks on display are very pretty. To get to the museum you need to walk in the main entrance of the institute and ask the security guard.  Someone from the museum will then come and meet you and escort you to it. It is free of charge although you have to pay to take photos.