The construction of Holy Trinity Cathedral, entrusted by Catherine II to architect Ivan Starov in the late 18C, completes the Alexander Nevsky Lavra. Quite unlike the Orthodox tradition, with a single dome and two bell-towers framing a classical facade, the lavish interior boasts fine decorations including an altar in white marble and red agate, adorned with copies of works by Rubens, Van Dyck and Guerchin, and the silver reliquary of Alexander Nevsky.