Among the ruins, Russell Maclennan-Jones imagines life in ancient Ostia.
"It's just a lot of ruins," moaned one visitor to Ostia Antica just outside Rome, but the people in my group smiled because our guide Massimo had been bringing a whole city to life for us.
In fact, some ruins are impressive on their own account - a theatre capable of seating thousands, bath complexes, a forum with a host of shops. But you need a bit of help to imagine the 50,000 people from all over the world who thronged the city at the height of the Roman Empire.
For that reason it's worth taking a tour (I chose Viator) and if you are lucky you will get someone as knowledgeable and enthusiastic as Massimo.
He explained how the city had grown up at the mouth of the Tiber and became one of the most important ports in the world.