The Tiber does its last bit of meandering here, between the airport at Fiumicino, the exhibition halls of the Fiera di Roma and a scatter of new suburbs at Ponte Galeria and Parco Leonardo. On a map it looks like nothing much, a tangle of motorway junctions on the western fringe of Rome, and on the ground it is mostly that. But it is a very old landscape under the concrete, and if you have ridden down from the Val d'Orcia, it is worth knowing what you are arriving into.
This was Rome's door to the sea. The ancient city's port was at Ostia, at the mouth of the Tiber, and when that silted up, the emperors Claudius and Trajan built a vast new harbour a few kilometres north, near today's airport. Trajan's basin, a perfect hexagon cut into the land, still holds water, surrounded by woods, and you can see it clearly from a plane landing at Fiumicino. Grain from Egypt and North Africa came through here to feed a city of a million people, and it was dragged up the river on barges pulled by oxen along the towpaths. Ostia Antica, a short ride south, is one of the great archaeological sites of Italy, a whole Roman town of streets, warehouses, baths and apartment blocks, and on a quiet weekday it is far less crowded than the Forum.
The road in from Tuscany is usually the A12 motorway from Civitavecchia, or the old Via Aurelia that runs beside it, both flat and quick along the coast, with the sea glinting between umbrella pines on the right and the Tolfa hills on the left. After hours of cypress avenues, cream-coloured hills and the long climbs around Pienza and Radicofani, it is a deliberate wind-down. Traffic thickens fast once the airport signs appear, and the junctions around the Fiera can be confusing, so read the signs early. Expect gusty sea wind on the open stretches in the afternoon.
Practically, everything is here: fuel stations on all the main roads, a big shopping centre at Parco Leonardo with food of every kind, and trains to Rome and to the airport, which makes it handy for anyone flying home or meeting someone off a plane. A quiet tip for the last hour of daylight: ride the few kilometres to the beach at Fregene or Focene, sit with your back to the pines and watch the sun go down into the Tyrrhenian before you face the city.