The fort at Isca is a neat, ordered Roman structure atop a mountain called Red Mount in first-century Britain, with the "sprawling huddle" of a little town spread below. The fort is lofty, in contrast to the rough, earthy, reed-thatched huts of the village. The entry to the fort is a majestic Praetorian gate, and the ramparts are made of rammed turf and stone. (Chapter 1).
The officers and legionnaires of the cohort Standard are housed in "one small square of wattle-and-daub buildings round a colonaded courtyard" within the fort. In addition to sleeping quarters and offices are a bath-house and a shrine where the Standard is kept. The buildings are decorated randomly with drawings scratched out on the walls, there is a martin's nest under the eves of the shrine, and in the corner of the officer's coutyard there is a rose-bush in a large stone jar. All of this area is protected by a succession of Roman sentries, who pace up and down between guardposts on the rampart around the clock, watchful and alert (Chapter 2).