The Danube makes a border here, and so it did two thousand years ago. On the north bank, at Iža in what is now Slovakia, stood the Roman fort of Celemantia, and on the south bank, near Almásfüzitő, another fort called Azaum guarded the Pannonian shore. Together they were part of the Danube Limes, the river frontier of the Roman Empire, and UNESCO listed sections of it in 2021. Close by, at Szőny, lay Brigetio, a legionary base and a real town with an amphitheatre. The river was the road, the wall and the defence all in one, and the legions patrolled it in boats.
The modern border towns of Komárom and Komárno share a story that is half Roman, half Habsburg. They were one town until the treaty of 1920 drew the border down the middle of the Danube, and now Komárom lies in Hungary and Komárno in Slovakia, joined by a bridge. Komárom has a huge nineteenth-century fortress, the Monostor, one of the largest in Central Europe, and the old town has a market square with a plain, handsome look. The fort at Iža is a Slovakian site and the nearby Hungarian bank has several others.
The riding is flat and straightforward, along the broad Danube plain, with fields of sunflowers and wheat and a distant line of low hills. The roads are decent but often busy with lorries, because the main road from Budapest to Vienna and the motorway cross this country. Back lanes along the river are quiet, with a few villages and the odd fisherman's hut. A strong wind is common, and in summer the air is hot and heavy. Early autumn, when the light is long and gold, is the pleasant time.
Komárom has nearly twenty thousand people and good fuel and food, and Komárno across the bridge is bigger. Both have thermal baths, since this part of Hungary sits over hot water. Try a bowl of halászlé, the paprika fish soup of the Danube, at a riverside restaurant, and finish with a coffee. Bring your passport for the bridge, though the border is open now, and be ready for the heavy traffic in the centre.