The palace is by far the largest known Roman residence north of the Alps. At about 500 feet (150 m) square, it is larger than Buckingham Palace. It is about the size of Nero's Golden House in Rome or the Roman villa at Piazza Armerina in Sicily. In plan it closely mirrors the layout of the emperor Domitian's palace, the Domus Flavia, completed in AD 92 on the Palatine Hill in Rome.