The Myatlev’s house is the oldest building on St. Isaac’s Square, having not once changed its original facade.
It was built in 1760’s in the northwestern corner of the square for Count Lev Naryshkin, and was later acquired by the Myatlev family. It is not known who designed the house, but Antonio Rinaldi, Yuri Felten, and Jean-Baptiste Vallin de la Mothe have all been speculated to be the architect.
Its façades are embellished with large medallions and busts, long reliefs depicting classical processions and compositions of armor.
The French philosopher and materialist Denis Diderot lived in the house in 1773-1774 on his visit to St. Petersburg.
A granite memorial plaque in his honor was put up on the front of the building in 1991, saying in Russian and French:
В этом доме с 8 октября 1773 по 5 марта 1774 жил великий французский просветитель Дени Дидро
Dans ce batiment D’Octobre 8 1773 A’Mars 5 1774 vecut le grand Philosophe francais Denis Diderot