Ljubljana or Mostar?

Both cities are inland, so neither is a swimming base, but the swims they offer are different. From Ljubljana you swim in the Sava or an Alpine lake: Bled is the warmer lake and Bohinj the clearer one. The Slovenian coast at Piran is mostly concrete platforms and pebbles.

The Neretva in Mostar is too cold for more than a quick plunge from the rocks. The pool under the Kravica waterfalls, though, is a proper summer outing, and the Adriatic at Neum is a little closer to Mostar than Piran is to Ljubljana.

Ljubljana gives you more to eat and drink. There is the Central Market under Plečnik's colonnades, gostilna inns serving štruklji and jota, and a handful of modern Slovenian kitchens. Above all there is wine by the glass from Vipava, Brda and Styria, including the orange wines of the west.

Mostar's cooking is narrower: charcoal-grilled ćevapi in somun, burek and slow-cooked stews, with Žilavka and Blatina to drink and Bosnian coffee as a slow ritual. It satisfies for a few days, but there is little beyond Bosnian home cooking.

The two are evenly matched, but their appeal is different. Ljubljana's comes from a whole townscape shaped by Plečnik: the bridges, the embankments, the library and the castle on its hill. Galleries and the murals of Metelkova add to it.

Mostar is built around one dramatic monument, the rebuilt Ottoman bridge. Around it are the bazaar street, a minaret you can climb, carpeted Ottoman houses and war-scarred façades along the old front line, which give it a rawer history than Ljubljana's.

Ljubljana has more going on after dark. Terraces line both banks of the Ljubljanica and stay full on warm evenings, students keep the city livelier during term, and Metelkova's scruffy clubs stay open late at weekends.

In Mostar a night out usually means a long dinner with a view of the lit bridge, after which the old town goes quiet. A few cocktail bars and student clubs stay open later on summer weekends, and that is about all.

Ljubljana has true Alpine country on its doorstep, and the green starts inside the city. Tivoli Park climbs into forested hills, locals walk up Šmarna Gora before work, and the Kamnik-Savinja Alps and Triglav National Park are each within about an hour. Add rafting on the Soča, the Postojna and Škocjan caves and skiing at small resorts in winter, and there is something to do outdoors in every season.

Mostar's surroundings are wilder and barer: a hot karst basin under the limestone ranges of Velež and Prenj, with rafting in the Neretva canyons, the Buna spring at Blagaj and migrating birds at Hutovo Blato. The trails are rugged and the valley summers are fierce, so walking there is mostly for spring and autumn.

Ljubljana sits in the middle of Slovenia, so most of the country is within reach. Bled, Škofja Loka, Radovljica, Predjama Castle, Lipica, Idrija and Piran all make easy day trips, buses and trains reach the main ones, and Trieste and Zagreb add two more countries.

Mostar's excursions are fewer and smaller: the dervish house at Blagaj, Počitelj on its hillside, the stećci tombstones at Stolac and the wartime sites at Jablanica and Konjic. Sarajevo is the one big name and makes a long day by train. Most of the other trips need a car or a tour.

Ljubljana is the easier city with children. The centre is flat and calm, so pushchairs cope well, and the dragons on Dragon Bridge, the science centre and the lawns and playgrounds of Tivoli keep young children busy for two or three days.

Mostar works for a day or two. Restaurants welcome children warmly, and the bridge divers are a highlight. Against that, the steep, polished lanes defeat pushchairs, and the summer heat in the valley is hard on small children.

You can walk both centres, but Ljubljana's is flatter and mostly pedestrianised, with electric shuttles and a bike-share scheme as backup. Intercity buses also make trips into the country simple without a car.

In Mostar the old town and the bridge are a short stroll apart on worn, slippery cobbles. Beyond them, the city buses are of little use to visitors, so Blagaj, Počitelj and Kravica mean a car, taxi or tour. The train to Sarajevo is the main link beyond the city.

Neither city is a shopping destination, and both are small in scale. Ljubljana's best buys are food or crafts: honey, pumpkin-seed oil, salt from the coast and Idrija lace, plus a Sunday flea market on the embankment and a few design boutiques.

Mostar's shopping is one bazaar street, the Kujundžiluk. Hand-hammered copper coffee sets and kilims are sold there among a lot of imported souvenirs, so look for a craftsman working in a doorway.

Mostar is noticeably cheaper. Guesthouses, grilled meals, local wine and coffee all cost little. Only the terraces with bridge views and old-town rooms in midsummer push prices up, and a few streets away they come back down.

Ljubljana is middling for Europe. Set lunch menus and the short walking distances help, but central rooms in summer cost as much as in Western Europe, so you will spend more on accommodation there.

Ljubljana is far stronger for live performance. The Slovenian Philharmonic, the national opera and ballet, the year-round programme at Cankarjev dom and the summer festival in Plečnik's Križanke courtyard give you a real chance of a good concert or an opera night.

Mostar has a national theatre and a youth theatre, both performing mostly in local languages, and some open-air concerts in summer. For much of the year, live music there means the odd band in a café bar.

Neither city has a bathing tradition, but Ljubljana offers more. There is a large water park with a sauna complex and a few hotel spas in the city, and real thermal bathing is about an hour's drive away in Slovenia's spa towns.

Mostar's Ottoman hammam is a historic building rather than a working bath, and spa treatments are limited to a few hotels. Its restful side is unhurried coffee in the shade and the quiet by the river once the coach groups have left.