A great rectangular enclosure of crude bricks, measuring about goo X 850 ft., contains the sacred buildings: it was entered by two stone gateways, in the north and the east sides, built by Domitian.
Doorways were usually square, but corbelled archways and gateways surmounted with sculptures were not uncommon.
Round the base is a flagged pathway surrounded by a stone railing and entered at the four points of the compass by gateways some 18 ft.
Both gateways and railing are elaborately covered with bas-reliefs and inscriptions.
In the 11th century the area was enclosed by earthen ramparts, with bastions and gateways; but of these the only surviving remnant is the Golden Gate.