1. The Hermitage — probably the most famous museum in St Petersburg — is home to around 70 cats, which guard its treasures against rodents. The tradition dates back to a 1745 decree of Empress Elizabeth, the daughter of Peter the Great, founder of St. Petersburg.

  2. During WWII, Hitler planned to hold a huge celebratory banquet at Astoria Hotel once he'd conquered the city, and even had the invitations printed. Luckily for modern history he never did.

  3. Palkin Restaurant, one of the poshest eating establishments, owes its name to the original Palkin Café that opened in 1785. Literaturnoe (Literary) Café dates back to 1816 and is famous for being a favorite of Russia’s beloved poet Aleksander Pushkin.

  4. Couples place padlocks on ironwork, bridges and even trees around downtown St. Petersburg on their wedding day to symbolize the security of their marriage. The Kissing Bridge gets "de-locked" every three months.

  5. "Why does St. Petersburg have one of the deepest subways in the world? Because they had to dig below the permafrost." The joke is based on the fact that on average, metro stations here are situated some 60 — 70 meters below the ground, and Admiralteyskaja Station is 120 meters deep because of a high water table. But permafrost sounds a lot better.