The Cathedral of the Intercession of the Most Holy Theotokos on the Moat, also known as Saint Basil's Cathedral, is one of the most important monuments of ancient Russian architecture from the 16th century. It was built between 1555 and 1561 on the orders of Tsar Ivan the Terrible in honor of the conquest of the Kazan Khanate.

The central church of the cathedral is dedicated to the Intercession of the Most Holy Theotokos. Four other churches, dedicated to the Three Patriarchs of Constantinople, Cyprian and Justina, Alexander of Svir and Gregory of Armenia, are consecrated in honor of saints on the days of memory when significant events of the military campaign took place. The program of church dedications also reflects other important events in Russian spiritual life in the second half of the 16th century, such as the appearance of a new icon of Saint Nicholas the Wonderworker in the Vyatka lands and the glorification of the venerable Varlaam of Khutyn and Alexander of Svir. The eastern church is dedicated to the Holy Trinity, the main dogma of the Christian faith, while the western church of the Entry of the Lord into Jerusalem symbolically connects the cathedral with the image of the Heavenly City.

Saint Basil's Cathedral is known for its unique wall paintings, a rich collection of ancient Russian iconography, and masterpieces of church applied art. The ensemble of ten churches with complete iconostases and interiors reflects the four-century history of the temple.