The Roman Emperor Septimius Severus was the only Emperor to come from Leptis Magna, the magnificent harbour town of Libya. Leptis is now out of bounds, but an equally great harbour survives just outside Rome. Ostia should be a must for any visitor to Italy, once the coronavirus has come and gone! Its harbor is astonishingly well preserved, yet hardly anyone visits it. Perhaps it needs a novel to bring it to life? Meantime, its shops and houses are preserved up to three storeys in height, many of them with mosaics. It was from Ostia that the Emperor would have received all the stores and weaponry needed for his three years campaigning in Scotland, from 208 to 211 AD. He assembled the greatest Roman army ever: but what did the army do in Scotland? Where were the bridges Severus recorded on his coins? One enormous permanent bridge, and an even bigger boat bridge, perhaps joining England and Scotland?