In the interior of the station, as at Lincoln, York, and Borcovicus, the main street, or _via principalis_, led directly from the north to the south gate.[18] The centre of the station, west of the _via principalis_, was occupied by the _praetorium_, the headquarters of the commander of the legion, answering to the space where, in a temporary camp, the tents of the general and his staff were pitched. As we have seen, the place of the _praetorium_ was taken in commercial towns by the _forum_. The _praetorium_ at Borcovicus consisted of two rectangular courts, open to the sky in the centre. The outer court, with its main entrance facing the eastern street or _via praetoria_, was surrounded on three sides by a colonnade. A doorway, immediately opposite the main entrance, opened into the eastern colonnade of the inner court. This had no northern or southern colonnades, but had doorways to north and south: its western side was occupied by a line of five rectangular chambers, the central one of which was the chapel where the standards, with the other sacred treasures belonging to the cohort,[19] were kept. The _praetorium_ faced the eastern street of the station, which led to the east gate or _porta praetoria_. The gate at the end of the western street was called _porta decumana_.[20] The remaining buildings of the station consisted of straight blocks, intersected by lanes: the majority of these buildings would be used as barracks. It should be noted that, in the planning of a Roman station or walled town, the _praetorium_ or _forum_ was taken as the central point: the _via principalis_, in order to run clear from gate to gate, was thus on one side of an axis of the rectangle, and the north and south gates[21] were not in the centre of their respective walls.