St. Sophia Cathedral: masonry

St. Sophia Cathedral is built of limestone on lime mortar with an admixture of red crushed brick (so-called 'tsemyanka'). Stones (Volkhov limestone) of arbitrary shape are cut only along the planes of the walls. In the picture there is a gallery of the southern part with cleared walls and with floors exposed to level XI, located 1.3 m below the modern floors. You can look, but you can’t go down and follow in the footsteps of your ancestors, because it’s fenced off.