Saint Isaac's Cathedral is one of the famous attractions of Saint Petersburg. It is one of the world's top dome structures. Excursions to St. Isaac's Cathedral are very popular because of its really impressive sizes. St. Isaac's Cathedral concedes in the dome size only to the St. Paul's church, located in London, or the church of St. Peter in Rome. The area of the cathedral is four thousand square meters. Such enormous size allows the cathedral to accommodate up to twelve thousand people. By choosing an excursion to St. Isaac's Cathedral, you will be able to see this architectural wonder with your own eyes. Your tour guide will tell you some interesting facts about the cathedral and the nuances of its construction. For example, the fact that it took 100 kilograms of pure gold to gild the domes and in construction of walls were used forty three different rock minerals.