At Celei, a few kilometres from Corabia on the Danube, the Romans built a bridge. It is a thing worth pausing over, because the bridge was built in AD 328, in the time of Constantine the Great, and it linked the Roman fortress of Sucidava on the northern bank with the province on the other side. The bridge was nearly two and a half kilometres long, one of the grandest engineering projects of the late empire, and it gave Rome a way to project power across the river long after the rest of the frontier had begun to crumble. A later emperor, Justinian, rebuilt Sucidava in the sixth century, and the fortress was in use for a very long time.
Today, you see low walls, foundations and a few towers on a field beside the river, with a small museum in Corabia that holds the finds. Like many Roman sites on the Danube, it is more evocative than spectacular: you have to bring your imagination, and the wind off the water helps. Sunsets here are wide and slow, and the river is broad, brown and busy with barges. On the opposite bank, in Bulgaria, you can see the low hills and the town of Somovit.
Corabia is a port town of about twenty thousand people, with a long promenade, a grain port and a modest, rather melancholy charm. It has fuel, cafes and a few restaurants, and Orlea, next door, has a market. The roads in the area are straight, flat and sometimes cracked, with potholes after winter, and the traffic is mostly trucks, farm machinery and the occasional horse cart. The best riding is on small roads along the river, where you can stop at a fisherman's shack for fried fish and a cold beer.
The Danube here is a source of life: carp, catfish and the occasional sturgeon, and in spring the floodplain is full of birds. Summers are hot and can be dusty, so the best months for riding are May, June and September.