Karlovy Vary or Vienna?

Neither city has a coast, but Vienna is clearly better for swimming in summer. The Danube Island gives about 20km of free bathing spots and the Alte Donau has old lidos where locals swim after work, all reached by U-Bahn.

Karlovy Vary has no real equivalent. Lake Medard, a flooded mine half an hour away, and the warm spring-fed pools are the options, which is fine for a dip and no more.

Vienna has a cuisine of its own, while Karlovy Vary mostly serves solid Czech cooking. In Vienna you can move from schnitzel in a wood-panelled Beisl to Sachertorte in a grand coffee house, then on to Grüner Veltliner at a Heuriger among the city's own vineyards, with the Naschmarkt for casual meals.

Karlovy Vary offers roast pork, dumplings and svíčková, warm spa wafers from the colonnade stalls and Becherovka distilled in town. The riverside cafés suit a slow afternoon, but there is no market and few ambitious kitchens.

Karlovy Vary is worth seeing as a whole townscape more than for any single building. Its UNESCO-listed spa quarter is one short valley of pastel hotels and colonnades, best taken in on a slow walk from the steaming Vřídlo up to the columns of the Mill Colonnade. Its museums are small and specialist, so after a couple of unhurried days there is little left to tick off.

Vienna has a fine ensemble of its own in the old town and along the Ring. On top of that it has things Karlovy Vary cannot match: the palaces of a ruling dynasty, and art collections of world standing, from Bruegel to Klimt and Schiele. It also covers two eras, Habsburg baroque and the Viennese Art Nouveau of around 1900, so a week of sightseeing never starts to feel repetitive.

Karlovy Vary goes to bed early. Outside the film festival week, an evening means a hotel bar, a Czech pub or a casino, and the promenades are quiet by eleven.

Vienna is no party capital, but it gives you real choices: late bars and small clubs under the Gürtel arches, the Bermuda Triangle in the old town, deckchair bars on the Danube Canal in summer, and formal balls in winter.

These two are about level, and both have beech woods right on their doorstep. Karlovy Vary's forest rises straight out of the spa valley, with gentle paths up to the Diana tower, the Slavkov Forest moors nearby and skiing around Klínovec in winter.

Vienna's green land is more varied and more open. Vineyard trails lead up to the Kahlenberg, the Donau-Auen floodplain forest lies to the east, you can cycle along the flat Danube, and the Rax and Schneeberg give real mountains within reach.

Karlovy Vary has good outings close by. Loket's castle on the Ohře is twenty minutes away, the sister spa towns of Mariánské Lázně and Františkovy Lázně are about an hour away, and you can see the reliquary at Bečov. Plzeň is also within reach, though Prague means a long coach day.

Vienna's position gives it the wider spread. Bratislava is an hour away by train or boat, the Wachau has Melk and Dürnstein along the river, and the abbeys, the Haydn palace at Eisenstadt and the Neusiedler See wine villages are easy days.

Vienna is far easier with children. Schönbrunn Zoo, the Prater's Ferris wheel and rides, the dinosaurs at the Natural History Museum and the ZOOM children's museum fill days in any weather, and trams take prams easily.

Karlovy Vary is safe and pleasant, but it is built around adults taking cures. The geyser, the funicular to the Diana lookout, the thermal pool and a trip to Loket castle will keep children happy for a short stay, and the steep slopes are hard work with a pushchair.

Vienna is one of the simplest cities in Europe to move around. It has a walkable old town inside the Ring, five U-Bahn lines, dense trams and one ticket for all of it, with night trains at weekends.

Karlovy Vary is easy on foot along its narrow river promenades, but the valley sides are steep, so you will use the buses and funicular. Regional trains to nearby towns are slow, and a car helps for the forests and villages.

The gifts in Karlovy Vary are specific and worth buying: Moser crystal from its own showroom, local porcelain, Bohemian garnets and Becherovka. Beyond the boutiques on Stará louka there is little range and no market of note.

Vienna offers more variety. It has luxury houses on the Kohlmarkt and Graben, everyday fashion on Mariahilfer Strasse, independent designers in Neubau, Augarten porcelain and Loden coats, a Saturday flea market and Christmas markets.

Karlovy Vary is the cheaper stay of the two. The colonnade restaurants and grand hotels charge for the setting, but one street back the pubs serve Czech food and beer at local prices, and the springs and promenades are free. Avoid the festival week, when rooms are dearest.

Vienna is a mid-to-upper Western European capital. Set lunches, sausage stands, free palace gardens and opera standing places help, but full museum admissions and hotels during the ball and Christmas market seasons add up.

For live music, Vienna is in a different league. The State Opera stages a different work on most nights, the Philharmonic plays in the Musikverein's Golden Hall, and the Konzerthaus, Volksoper, Burgtheater and Vienna Boys' Choir complete a programme that runs all year.

Karlovy Vary offers a pleasant night out rather than a scene. Its symphony orchestra plays light classics, sometimes outdoors on the colonnades, and the Fellner and Helmer theatre takes touring drama and operetta.

Taking the cure is what Karlovy Vary was built for, and it does this far better than Vienna. You walk the colonnades sipping warm mineral water from a spouted porcelain cup, and dozens of spa hotels and sanatoria offer medical stays with treatments, massages and pools of spring water. There is also an outdoor thermal pool on the hillside. Public bathhouses are few, so book a spa stay to get the full experience.

In Vienna, rest is more casual. It comes from long coffee-house afternoons and walks in the palace gardens, with thermal pools at Therme Wien, the Art Deco Amalienbad and nearby Baden. But bathing sits alongside city life here rather than at its centre.