The Danube flows broad and brown past Zwentendorf, a quiet village on the Tullnerfeld plain west of Vienna, and for once the most famous building in the area is not the oldest one. Zwentendorf is where Austria built a nuclear power station in the 1970s and then, after a national referendum in 1978, decided never to switch it on. The plant still stands by the river, complete and unused, now a training site and a curiosity.
The older story lies quietly in the fields. Under the turf near the village are the remains of a Roman fort on the Danube Limes, the frontier line that ran along the river protecting the province of Noricum from the peoples to the north. A chain of forts, watchtowers and small towns lined this bank, and the whole system is now part of the Frontiers of the Roman Empire World Heritage site. There is not much above ground to see here, so bring imagination: picture a rectangle of walls, barracks and gates, with soldiers watching the far bank for raiders crossing on the ice in winter.
The land around is flat river country, maize and sugar beet fields, poplars along drainage channels and floodplain woods by the Danube. The riding on the plain itself is straight and simple, with the occasional crosswind, but the hills on both sides are where the fun begins. North of the river, the Wagram escarpment rises in a long bank of terraced vineyards growing Grüner Veltliner, with villages of wine cellars and some fine twisty lanes. To the south, the Dunkelsteinerwald forest offers quiet wooded roads, and a short ride west brings you into the Wachau, one of the most beautiful river valleys in Europe, which is worth a day on its own.
Tulln, about thirteen kilometres east, is the town for fuel, food and supplies. It is also the birthplace of the painter Egon Schiele, and has a museum to him in the old jail building by the river, as well as a riverside promenade and a famous garden show. Zwentendorf itself has a few local services, a church and the riverbank, which makes a pleasant place to sit and watch barges pushing upstream against the current.