Earlier in the area of Admiralty there was a small wooden church dedicated to Saint Isaac of Dalmatia, which replaced another stone, which was useless in the mid eighteenth century. Finally, in the early nineteenth century, they decided to build the new cathedral. Participate in the contest leading architects of that time. Sale won by the young French architect Auguste Montferrand. The work lasted from 1818 to 1858.

In the decoration of St. Isaac's Cathedral were used 43 types of minerals. The base was covered with granite, the interior of the cathedral, with marble walls and floors Russians, Italians and French, the columns of the altar were covered with malachite and lapislazuli. For plated, dome 21.8 m in diameter, were used about 100 kilos of gold. Adorn the cathedral nearly 400 works including sculptures, paintings and mosaics. It has capacity for 14 thousand people.

Since 1931 the cathedral is a museum. You can climb up the drum of the dome, which affords a magnificent view of St. Petersburg.