The plateau itself rose up to a summit, where a beacon bonfire had been built. Some of the flatter ground had been given over to cultivation, but there would be little farmland up here. Artorius’s capital would be fed by farmsteads on the plain outside the fort. Part of the bargain behind this was that the farmers would be able to huddle inside the walls in times of danger. In a lower part of the plateau a wooden hall was being built to house Artorius himself. The burned-out remains of a much older building had been cleared—perhaps the home of some chieftain of pre-Roman times.

They walked around the edge of the plateau. A perimeter wall was being constructed—or rather reconstructed, she saw, based on the foundations of some ancient predecessor. It would be five paces thick, a framework of wooden beams filled with stones, most of them coming from the Durnovaria cemetery. Already the framework skirted most of the plateau, and work had begun on a large, complex gate in the southwest corner. Regina was impressed with the scale of all this, and the efficiency of Artorius’s organization.

“You are able to command the work of hundreds.”

Artorius shrugged. “They tell me that the emperors once commanded a hundred million. But one must start somewhere.”

There had been rain, and the grass-coated slopes of the hill were intensely green. The slopes were surrounded by lines of banks and ditches. Men were working their way over the forested banks, cutting down trees with their iron axes and saws and hauling the trunks to the summit of the hill.

They were making the rings of ditches into a defense system. Artorius pointed. “There are four lines. See how we look down on the earthworks? The Saxons will have to run up that slope, arriving exhausted, and then down this face below us, where they will offer an easy target to our arrows or spears. The banks are overgrown with trees—three or four centuries’ growth, I suppose, quite mature—and the slopes need to be cleared to avoid giving cover to any assailants, but we can deal with that.”

“It is a lucky arrangement of ditches and ridges to be so useful.”

He looked at her quizzically. “Luck has nothing to do with it. I thought you understood—Regina, there is nothing natural about those ditches. Everything you see was dug out by hand—by our ancestors, in fact, in the days before the Caesars.”

She could scarcely believe it. “This is a made place?”

“It certainly is. It looks crude, but is well thought out. The fort is a machine, a killing machine made of earth and rock.” He scratched his chin. “The work required to assemble even our paltry new wall is enormous. To have sculpted the hill itself—to have built those banks and ditches—defies the imagination. But, once built, it lasts forever.”

“And yet the Caesars cleared out this place, as mice are cleared from a nest.”