Originally Posted by
TheMadBrewer
The people I know that enjoyed St Petersburg all did it from a cruise ship docked in the harbor for a few days -- though this was a while ago so and was for safety reasons so that may not apply today.
I think it is not that much about security, but the Russian visa policy, which does allow short (up to 72h) visa-free visits if you arrive by sea. And in addition to the fancy cruise ships on grand Baltic tours, there is
St. Peter Line which offers visa-free cruises to St. Petersburg from Stockholm via Helsinki/Tallinn. And of course it is possible to extend the stay in Russia if you are willing to get a visa.