Nagasaki or Osaka?

Neither city is made for a beach vacation, but Nagasaki has slightly the better swimming. About an hour by bus down the peninsula, Takahama's clean sand looks straight out onto open water, not a closed-in harbour. Iojima's small resort beach is a short ferry hop from the city, and the season runs on into early September, when the jellyfish arrive.

Osaka's summer beaches at Suma, Nishikinohama and Tannowa take about as long to reach by train. They lie on an enclosed, heavily built-up bay, though, with coarse sand and suburbs behind them, and they are open for little more than July and August. Locals treat them as a day out with friends, and in either city a swim is a break from sightseeing rather than a reason to go.

Eating is the main reason to come to Osaka, and it beats Nagasaki easily. Osaka has street griddles of takoyaki, okonomiyaki cooked at the table, kushikatsu counters, Kuromon Market and the cramped izakaya of Ura-Namba and Tenma. At the top end there are the kaiseki and sushi counters of Kitashinchi, and few places in Japan offer as much range.

Nagasaki's cooking is more unusual but much narrower. Champon, sara udon, castella and the shared shippoku banquet carry its Chinese, Portuguese and Dutch past, and the local fish is excellent in the Shianbashi izakaya. You will eat well there, but within a few days you will have tried most of it, and there is little fine dining.

Nagasaki has the stronger set of sights, because they all belong to one story. The Atomic Bomb Museum and the hypocentre in Urakami stand alongside Dejima's trading post, the merchant houses of Glover Garden, Oura Cathedral and the Ming-style Sofukuji. Together they explain why this city's history is different from the rest of Japan's.

Osaka's heritage comes in separate pieces. There is the reconstructed castle on its original walls, Shitennoji and Sumiyoshi Taisha, and the ceramics and art museums on Nakanoshima. Much of what is worth seeing is the modern city itself, from the neon of Dotonbori to Shinsekai under Tsutenkaku tower.

Osaka is one of Japan's great cities for a night out. Nagasaki is a pleasant place for a quiet drink. In Minami you can bar-hop through Dotonbori, the standing bars of Ura-Namba and the small clubs of Amerikamura. Strangers chat at the counter, and plenty of people stay out until the first train.

Nagasaki's evenings centre on Shianbashi, an old grid of izakaya, karaoke and snack bars, many of which mainly serve regulars. Grilled fish and sake are easy to find, but the streets empty early. For many visitors the best part of the evening is the night view from Mount Inasa.

The two are about level outdoors, but the landscapes are very different. Nagasaki itself is the scenery: a deep harbour ringed by steep green hills, with the ropeway up Mount Inasa and the rocky Nomo coast nearby. Two hours away, Unzen has volcanic vents and the climb up Mount Fugen.

Osaka is flat concrete, and its green escapes lie within an hour by train. Minoo's forest trail climbs to a waterfall, and there are ridge walks in the Rokko mountains above Kobe. These are easier to reach than Nagasaki's wilder places, but they are gentler and suit day walkers.

From Nagasaki, the outing everyone remembers is the boat to the concrete ruins of Gunkanjima, though whether you can land depends on the weather. After that the distances grow. Shimabara and Unzen, the porcelain towns of Arita and Imari, and Hirado each take a long day, and the churches of the Goto Islands need a night away.

Kyoto, by contrast, is under half an hour from Osaka by train, and Nara about forty minutes. Kobe is closer still, and Himeji Castle, the tea houses of Uji and the monasteries of Koyasan are all easy to reach. With trains this frequent and quick, you could spend two weeks on day trips without ever changing hotel.

Osaka is much the easier city with children. Universal Studios Japan is a short train ride from the centre, the Kaiyukan aquarium has whale sharks in its huge central tank, and Tennoji Zoo, Kids Plaza and Expo '70 Park fill any days left over. Stations and department stores have lifts and baby rooms.

Nagasaki has gentler treats: trams, the ropeway, the Penguin Aquarium where the birds walk out onto a beach, and a big day out at Huis Ten Bosch. Its stepped hillside streets are hard going with a pushchair, though, and the Atomic Bomb Museum needs some thought with younger children.

Osaka's subway and JR network covers far more ground. The Midosuji line links Umeda, Namba and Tennoji, and the same IC card takes you on to Kyoto, Nara and Kobe. The catch is the stations themselves: changing lines inside the Umeda maze can take a long walk.

Nagasaki is simpler but smaller. A handful of flat-fare tram lines run along the valley floor past nearly every sight. Once you leave that valley floor, though, getting anywhere means climbing steps up the hillsides.

For shopping, Osaka is in a different league. It has the long Shinsaibashi-suji arcade, the old department stores and food halls of Umeda, international flagships on Midosuji, vintage clothing in Amerikamura and the electronics and anime shops of Den Den Town. Kitchen knives from Doguyasuji are the souvenir to remember.

Nagasaki's Hamanomachi arcade covers everyday needs, and the best things to buy are local. Look for boxed castella, glassware and porcelain from Hasami, Mikawachi and Arita, which is easier to find here than in Osaka.

Both are fair-priced by Japanese standards, so the difference is in where the money goes. In Nagasaki, rooms and meals stay modest, and the costs build up with the Hashima boat tours, the ropeway and long evenings of sashimi and sake.

In Osaka, food is the great bargain, from takoyaki to izakaya meals. The pressure falls on rooms in cherry-blossom and autumn-leaf season and at weekends, and on big tickets such as Universal Studios Japan.

Osaka has a proper stage culture. The National Bunraku Theatre puts on full puppet seasons with English guides, and kabuki comes to the city in seasonal runs. Festival Hall and Symphony Hall host concerts, there are live houses for rock and jazz, and the Takarazuka Revue's home theatre is close by.

Nagasaki's great performance is a festival rather than a season. The Kunchi brings three October days of dragon dances and ship floats to Suwa Shrine, and the Lantern Festival fills Chinatown around Chinese New Year. Outside those dates there is little to plan a trip around.

Bathing is easier to fit into an Osaka stay. Neighbourhood sento and large super sento complexes make an evening soak simple. Arima Onsen, one of Japan's oldest spa towns, is only about an hour away, close enough for an afternoon.

Nagasaki's best springs at Obama and Unzen really need an overnight stay at a ryokan. On the other hand, the city itself is calmer, with hillside temples and harbour walks, while Osaka is fast and noisy.