St. Petersburg is Russia's second-largest city with a population of over five million people. Still, almost everything you want to see is located in a comfortable distance from each other at the historical centre.
The city was built by Peter The Great in 1703 - right after it was conquered back from the Swedes. Peter, who grew up in Moscow and disliked his hometown, wanted to build a European style town in Russia. He was the first Russian Tsar to travel to Europe, spending over two years travelling around with his entourage.