This is a fine example of a working Orthodox monastery, with military features that are typical of the 15th to the 18th century, the period during which it developed. The main church of the Lavra, the Cathedral of the Assumption (echoing the Kremlin Cathedral of the same name), contains the tomb of Boris Godunov. Among the treasures of the Lavra is the famous icon, The Trinity , by Andrei Rublev.

Źródło: World Heritage Convention
http://whc.unesco.org/en/list/657