The lighthouse was centuries old. It had been constructed, like the port itself, by the Emperor Claudius, who had conquered Britain. But though its concrete fascia was weathered and cracked, it surely stood as solid and intimidating as the day it was constructed. As she passed, Regina could see how it was founded on a sunken ship, whose outlines were dimly visible through the murky, litter-strewn water. The story was that this great vessel had been built to transport an obelisk from Egypt, and then filled with concrete and deliberately sunk. The huge old lighthouse loomed over the ship, utterly dwarfing it. But the crew seemed oblivious to its presence, and Regina tried not to cower.

Inside the harbor, the water was a little calmer—but this harbor was so vast it was itself like an enclosed sea. Ships of all sizes cut across its surface. Most of them were wallowing cargo ships, decorated with the dark green of the imperial navy: grain transporters, scores arriving here every day from Italy and Africa. The seamanship required to maneuver these huge ships in such cramped and crowded conditions impressed Regina, and there was much mocking rivalry between the crews as they hailed each other across the narrow strips of water between their vessels.

Regina’s ship passed through this crowd and approached another concrete-walled entrance at the far end of the harbor. When they passed through, Regina found herself in yet another harbor, much smaller, a landlocked inner basin. It was octagonal in form and was lined with wharves and jetties, where ships nuzzled to unload their cargo. This harbor within a harbor had been constructed by the emperors to provide a port close to Rome capable of taking large oceangoing ships in all conditions. A canal had been cut from here to the Tiber, and grain and other goods were carried on smaller freshwater vessels to Rome itself. The engineering was mighty. This inner harbor alone could have swallowed the whole of Verulamium or Durnovaria, and the port complex would probably have drowned Londinium. But it was necessary; the flow of grain into the city could not be allowed to fail, no matter what the weather.

As the ship nuzzled toward a jetty, Regina tried to ignore the fluttering in her stomach. Already, long before reaching Rome itself, she was beginning to feel overwhelmed by the sheer scale of it all. Here in this bright, liquid Italian air, Britain seemed a remote, murky, underpopulated, undeveloped place, and everything she knew, all she had built, seemed petty indeed.

But she did not have time to be overwhelmed. She had a tablet on which was scrawled an address: that of Amator, the rogue son of Carausias, the last legacy of that stubborn old man. That address was where she would begin her Roman adventure—and where, she thought coldly, Amator would begin to pay back the debt he owed her.