The Roman frontier did not stop where Hadrian's Wall ended. At Bowness, on the Solway shore, the stone and turf barrier gave out, but a chain of small forts, fortlets and watchtowers continued south along the Cumbrian coast, past Silloth and Maryport to near St Bees, to guard against raiders coming across the water from Scotland and the Irish Sea. Archaeologists still argue about how it worked. Often only a faint platform in a field remains.
The coast here faces west across the Solway Firth, a wide estuary with some of the biggest tides in Britain, which race in over the sand flats faster than a person can walk. The hills of Dumfries and Galloway float on the far shore, and the sky is huge. Silloth, a few kilometres away, was built as a Victorian seaside resort when the railway arrived, with broad streets laid out in a grid and a long green that runs along the sea front. Today it is a quiet town where people eat fish and chips on the grass.
The riding is flat, wide and open. The coast road from Maryport to Silloth runs close to the shore, with long straight sections, a few gentle bends and big views, and in summer the traffic is light. The wind can be very strong and carries sand and salt, so keep an eye on the sky and on the cross-wind when passing gaps in the dunes. In winter the road is sometimes flooded at high tide. Sunsets over the Solway are among the best in England, and the light on the water changes minute by minute.
Silloth has fuel and a few cafes, and Maryport, thirteen kilometres to the south, has more. Aspatria is another option inland. A bag of chips by the sea, with a cup of tea from a small stall, is a classic Cumbrian lunch. Park, walk out onto the grass, and look at the frontier from the point of view of a sentry watching for sails.