Istanbul or Samarkand?

Neither is a beach destination, but only Istanbul offers swimming at all. Its long sandy strands at Kilyos and Sile on the Black Sea are about an hour away, with lifeguarded stretches to watch for currents, and the Princes' Islands add pebbly coves for a half day.

Samarkand lies deep in doubly landlocked Uzbekistan, so the only cooling off is in a hotel pool.

Istanbul draws on the cooking of the whole of Turkey, from Black Sea anchovies to south-eastern kebabs and Ottoman palace dishes, served in lunchtime lokantas, evening meyhanes and from street carts by the Galata Bridge. Kadikoy's market streets and the Spice Bazaar make grazing part of the sightseeing.

Samarkand eats well but narrowly. Its layered plov at lunchtime and the glazed round non bread from Siab Bazaar are worth seeking out, yet after a few days the shashlik and somsa start to repeat, and there is little beyond Uzbek and Russian cooking.

Both are among the great architectural cities of the Islamic world, and Istanbul goes a step further in sheer breadth. Hagia Sophia, Topkapi, the Blue Mosque and the Basilica Cistern share one peninsula, and the Chora mosaics, the Theodosian walls, Bosphorus palaces and major museums add layers of Byzantine, Ottoman and modern history that can fill a week.

Samarkand is more concentrated and, in its tilework, arguably more dazzling. The Registan's three madrasas, the mausoleum avenue of Shah-i-Zinda and Timur's gilded tomb at Gur-e-Amir are the core, with Ulugh Beg's observatory and the Afrasiyab murals around them, and three or four days covers it all.

Istanbul has a real night out: small bars and singing meyhanes off Istiklal Avenue, cocktail bars in Karakoy and Cihangir, cheaper bar streets in Kadikoy and Moda, and summer clubs on the Bosphorus that run to dawn.

Samarkand's evening is a long dinner, perhaps beside a wedding party dancing to a live band, and a walk past the floodlit Registan. A few hotel bars aside, the city is asleep before midnight.

Istanbul's outdoors is the water itself: walks along the wooded Bosphorus shore at Bebek and Rumeli Hisari, tulip-filled parks in April, Belgrad Forest trails and cycling on the car-free Princes' Islands. It is pleasant, easy and close at hand, though there are no mountains nearby.

Samarkand offers more rural country but needs more effort. The juniper and walnut valleys of Aman-Kutan and Urgut are about an hour out, with village walking trails, and summer heat limits hiking to spring and autumn, while the city itself has little green space.

Samarkand is the better base for outings, chiefly because Bukhara, a complete old town of madrasas and trading domes, is a fast train ride away. Shakhrisabz, Timur's birthplace, lies over a mountain pass, and the big Sunday bazaar at Urgut and the paper-makers of Konigil are close.

Istanbul's easiest escapes are by ferry, to the Princes' Islands or up the Bosphorus to Anadolu Kavagi. Bursa makes a good town day, but Edirne and Iznik are long, and simply leaving such a large city eats into the day.

Istanbul gives children far more to do. Ferry rides, the ships and submarine at the Rahmi M. Koç Museum, Miniaturk, aquariums and seaside parks on the Asian shore fill days, even if the crowds, hills and stairs tire small legs and pushchairs.

Samarkand is calm and safe, with wide pedestrian streets around the Registan, but its sights are mausoleums and madrasas in strong heat. It works mainly for older children curious about history, in spring or autumn.

Both are manageable without a car, but in different ways. Istanbul relies on a large network, with one card for metro, the T1 tram, the Marmaray tunnel, funiculars and ferries between continents, though rush-hour crowds and road traffic slow things down.

Samarkand is mostly a walking city, with the main monuments strung along one pedestrian street from the Registan to Shah-i-Zinda. For the observatory, Afrasiyab and the station, app taxis at fixed fares are simpler than the hard-to-read minibuses.

Istanbul is one of the great shopping cities, running from the covered streets and hans of the Grand Bazaar and the Spice Bazaar to designer boutiques in Nisantasi, Cukurcuma's antiques and Kadikoy's flea markets. Carpets, tiles, towels and tea glasses are easy to find, and haggling is part of it.

Samarkand's shopping is limited to crafts. Suzani embroidery, ikat silk, ceramics and mulberry paper from Konigil can be found in the madrasa cells of the Registan, but quality is uneven and there is nothing in the way of fashion.

Samarkand is the easier city on a modest budget. Plov, bazaar food, taxis and monument fees all cost little and guesthouses offer good value, with only upmarket hotels near the Registan and imported drinks pushing costs up.

Istanbul can be cheap if you live like a local, with low-cost ferries, simit and lokanta lunches. But hotels and menus in Sultanahmet and Galata, heavily taxed alcohol and steep entry fees at the big monuments add up quickly.

Istanbul has a proper stage scene: state opera and ballet at the Ataturk Cultural Centre, concert halls, summer jazz and music festivals in historic courtyards, and live rock and folk in Beyoglu and Kadikoy. Sema ceremonies in old dervish lodges and fasil musicians in the meyhanes are easy to catch.

In Samarkand, performance is mostly folk-dance shows for visitors and the Registan's sound-and-light displays. The Sharq Taronalari festival brings real musicians in some years, but maqom music is more often heard at weddings than on stage.

The hammam gives Istanbul a clear lead. Sinan's sixteenth-century baths, under domes pierced with star-shaped skylights, still offer the hot marble slab and a full scrub, and slow ferries and Bosphorus tea terraces offset the city's noise.

Samarkand's single old bathhouse near Bibi-Khanym and a few hotel spas are a footnote. Its rest comes instead from the slow pace, green tea on a shaded topchan and quiet old-quarter courtyards in the evening.