Interlaken or Piran?

Neither has sandy beaches with rows of sunbeds, but Piran is much the better place to swim. You can get into clear Adriatic water from the ladders and rocks along the seafront and around the Punta, or from the pebbles at Fiesa. Portoroz's small beach and the cliff-backed shore at Strunjan add sand and quiet, and the season runs all summer.

Interlaken's swimming is a summer extra. There are lidos and shingle on Lake Thun at Neuhaus, and a colder dip in turquoise Lake Brienz at Bönigen. It is lovely under the snow peaks, but cool and brief.

Piran eats better, though neither is a place to travel to for food. Grilled fish, squid and scampi buzara by the harbour come with Istrian olive oil, truffles and Malvazija or Refosk from the hills, and salt from the nearby pans, so meals feel local even when the menus repeat.

Interlaken's restaurants serve fondue, raclette and rösti alongside Indian and Asian kitchens. The food is reliable but forgettable. The best eating is up at hut terraces and mountain dairies, or in a supermarket picnic.

Piran is itself the sight: a Venetian Gothic peninsula of lanes and small squares around the oval Tartini Square, with St George's campanile and the old walls above. The museums are small: a maritime museum, an aquarium and the Minorite cloister. A day covers them, but the town is a pleasure to wander.

Interlaken has almost nothing to compare. The grand hotels and Kursaal along the Höheweg and a few timber houses in Unterseen are about all there is. For history and architecture you take the train to Bern or Thun.

Both towns go quiet early, but the evenings feel different. In Piran an evening means a glass of Malvazija on Tartini Square or a sunset drink on the Punta, with the beach bars, casino and summer clubs of Portoroz a few minutes away. Interlaken's evenings are younger and a little rowdier: backpacker pubs, sports bars and a couple of basement clubs near the hostels, busiest in summer and the ski season, plus the Kursaal casino.

Interlaken is one of Europe's great mountain bases. Within an hour lie the Eiger, Mönch and Jungfrau, the waterfalls of the Lauterbrunnen valley and the railway to the Jungfraujoch above the Aletsch glacier, and cable cars lift you onto high trails at First, Schynige Platte and Mürren. Paragliding, canyoning, rafting and winter skiing add to all this. Only low cloud gets in the way.

Piran's outdoors is pleasant but small in scale. It offers the flysch cliffs and coastal path at Strunjan, wading birds in the Secovlje salt pans, the Parenzana cycle route inland and the Skocjan caves on the Karst.

Both are strong bases, but for different kinds of outing. From Interlaken, trains and lake steamers reach Bern's arcaded old town, Thun's castle, the lakeside castles at Spiez and Oberhofen, Ballenberg's open-air museum and Lucerne over the Brünig Pass.

Piran's outings cross borders. You can reach Trieste's Habsburg squares, Rovinj, Porec and the Istrian hill towns of Motovun and Groznjan, as well as Predjama Castle, Ljubljana and, by summer boat, Venice. The range is wider, but harder to reach without driving.

Interlaken does more for children. Rack railways, gondolas and steamers are an adventure in themselves, and the summit stations have playgrounds, cliff walks and summer toboggan runs. The St Beatus caves and Ballenberg's farm animals add variety. The catches are wet days and altitudes that can trouble toddlers.

Piran is safe and car-free, with a calm, warm sea and a small aquarium. But swimming is off concrete ledges, the lanes are steep, and beyond the shallow sandy beach at Portoroz there is little else for children.

Interlaken is the easier place to explore without a car. Trains, cog railways, gondolas and steamers connect so neatly that the whole Jungfrau region and Bern can be reached by public transport. The flat town is a short walk between its two stations. Only summer crowds on the mountain trains spoil it.

Piran is simple on foot, with a car-free old town and a shuttle to the garage and Portoroz. But there is no railway and the regional buses are slow, so the Karst and Istria really call for a hire car.

Neither is worth a shopping trip, and both lean towards souvenirs. Interlaken's Höheweg is lined with watch and jewellery stores, army knives, cuckoo clocks and chocolate, and Brienz woodcarving is the one genuine local craft. Piran's best buys are things to eat and drink: sea salt and salt flower from Secovlje, Istrian olive oil and coastal wine, plus a few galleries in the lanes.

The gap here is wide. Interlaken charges full Swiss rates for rooms, meals and drinks, and the mountain railways, the Jungfraujoch above all, add a large sum on top. Hostels and picnics help only at the margins.

Piran is mid-priced for Western Europe. Old-town rooms and waterfront tables cost more in high summer, but staying in Portoroz or coming out of season brings the bill down to a fair level.

Both offer small-scale performance, mostly in summer. Interlaken's signature event is the amateur open-air William Tell in the woods, along with folklore evenings of yodelling and alphorns, and Bern's theatre and orchestra are under an hour away. Piran leans classical, with Tartini concerts in churches, the monastery cloister and on the square, and the little Tartini Theatre for recitals.

Piran is the more restful choice. Portoroz grew up as a spa town around seawater pools, brine baths and salt-pan mud, and there is an open-air thalasso spa among the Secovlje lagoons. The car-free town itself slows you down, especially in May, June and September.

Interlaken relies on hotel spas along the Höheweg and a public wellness area. The centre is busy with coach groups and backpackers, so calm is found on the lakeshore, aboard the steamers or up in Wengen and Mürren.