Under the eye of George Palaiologos Kantakouzenos, older brother of Despotina Jerina Branković, lumber, lime, and enormous stones from the former Roman cities of Mons Aureus (the modern village of Seone, west of Smederevo), Margum (at the mouth of the Great Morava), and Viminacium were collected. In the spring of 1429, Greek and Ragusan workers began the brickwork. In 1430, the elegant manor was completed. It included a palace stretching along the length of the moat wall; a throne hall against the Danube wall; a keep, "Donžon kula" (Donjon tower), in the corner formed by the walls; a treasury in a high chamber; and other auxiliary buildings, creating an inner city.