The Danube Trail Vienna to Budapest has some incredible points of interest (the largest cathedral in Hungary in Esztergom, the city of Gyor and the town of Tata, historically a place where the nobility of Budapest took their holidays). It is worth noting this route strays away from the Danube for a few days so you do not cycle right by it the whole way. The cycling to the city of Gyor is mainly on cycling paths, from here it is on paved backroads, with a few unavoidable streches on busier roads. The cycling is flat and easy for most of the tour. There is only one day with some hills but fortunately, one of the hills has a wine tasting restaurant on top.