The Palatine Hill, (Collis Palatium or Mons Palatinus; Palatino ) which is the centremost of the Seven Hills of Rome, is one of the most ancient parts of the city and has been called "the first nucleus of the Roman Empire." It stands 40 metres above the Roman Forum, looking down upon it on one side, and upon the Circus Maximus on the other. From the time of Augustus Imperial palaces were built here. Prior to extensions to the Palace of Tiberius and the construction of the Domus Augustana by Domitian, 81-96 AD, the hill was mostly occupied by the houses of the rich. The perimeter measures 2,182 meters and the area is 255,801 square meters or 63 acres, with a circumference of 1,740 meters while the Regionary Catalogues of the fourth century give a perimeter of 11,510 feet or 3,402 meters (equals 131 acres). The name of the hill is the etymological origin of the word palace and its cognates in other languages (Greek: παλάτιον, palazzo, palais, Spanish: palacio, Portuguese: palácio, Palast, palác, etc.).