This commanding cathedral on Nevsky Prospekt was modeled on St. Peter's Basilica in Rome, and its sweeping semicircular colonnade of 96 Corinthian columns dominates the surrounding streetscape. Built between 1801 and 1811 by architect Andrey Voronikhin, the cathedral houses the revered icon of Our Lady of Kazan and the tomb of Field Marshal Kutuzov, who defeated Napoleon's invasion of Russia. The Soviets repurposed it as the Museum of the History of Religion and Atheism in 1932, but Orthodox services resumed in 1992 and it now serves as St. Petersburg's mother cathedral. The interior is genuinely impressive, all soaring granite columns and soft candlelight. Entry is free.