St. Isaac's Cathedral is the largest cathedral in St. Petersburg and was the largest church in Russia when it was built. It was dedicated to
Saint Isaac of Dalmatia, a patron saint of Peter the Great who had been born on the feast day of that saint. The cathedral took 40
years to construct from 1818 to 1858. The cathedral is a late Neoclassical rendering of a Byzantine Greek-cross church. The
exterior features a total of 112 red granite columns with Corinthian capitals.