The Domus Aurea complex covered parts of the slopes of the Palatine, Esquiline, Oppian and Caelian hills, with a man-made lake in the marshy valley. Its size can only be approximated, as much of it has not been excavated. Some scholars place it at over 300 acres (1. 2 km2), while others estimate its size to have been under 100 acres (0. 40 km2). Suetonius describes the complex as "ruinously prodigal" as it included groves of trees, pastures with flocks, vineyards and an artificial lake—rus in urbe, "countryside in the city".