Vienna

Vienna rewards anyone who leaves the car at home. The City Airport Train runs nonstop from the airport to Wien Mitte in 21 minutes, and the cheaper S-Bahn covers the same ground a little more slowly, so the first decision of the trip is only about price. In town, the U-Bahn and the tram network reach the palaces, coffeehouses and the Prater, and trams climb toward the vineyards and wine taverns on the city's edge. Regional trains make the Danube's Wachau valley an easy day, with Melk Abbey at one end and Krems at the other, and Bratislava, a separate capital in another country, is close enough by train for lunch and a walk around the old town.