Hong Kong or Kaohsiung?

Neither city is a beach destination, but Hong Kong makes a swim easier to fit into the day. Repulse Bay and Deep Water Bay are a short bus ride from Central, the gazetted beaches have lifeguards and shark nets in season, and Cheung Sha on Lantau or the clear coves of Sai Kung offer quieter sand.

Kaohsiung's own shore is more for strolling than swimming. Cijin's dark sand suits sunset walks and seafood, and the sheltered swimming area at Sizihwan opens only in season. Its best water is on Xiaoliuqiu, where you can snorkel with sea turtles, but getting there takes a drive and a ferry.

Food is a main reason to visit Hong Kong, and it outclasses Kaohsiung in both range and refinement. Cantonese cooking is at its peak here, from noisy dim sum halls and roast meats in shop windows to wonton noodles, live seafood on Lamma and some of Asia's most acclaimed dining rooms in Central.

Kaohsiung eats well too, but more simply. Southern Taiwanese food is sweeter and built around seafood, so you start the day with milkfish congee at a market stall and end it queuing at Ruifeng for oyster omelettes and grilled squid. The cheap, informal food is the best of it, and there are few high-end tables.

Hong Kong has a little more to see, and much of its pull is the city itself: the skyline from Victoria Peak, the trams and the Kowloon tenements. M+ and the Hong Kong Palace Museum in West Kowloon give it museums of real weight, and Man Mo Temple, the Big Buddha and the walled villages add older layers.

Kaohsiung's sights reflect its life as an industrial port. The pagodas around Lotus Pond, the red-brick former British Consulate and the warehouse galleries of Pier-2 are the highlights, and two or three days covers them. Many visitors fill out the history with a trip to nearby Tainan.

Hong Kong gives you a real choice of nights out, and each district has its own character. In Central you can choose between the noisy weekend crowds drinking outdoors in Lan Kwai Fong and the quieter cocktail rooms uphill in Soho and Sheung Wan, and Wan Chai is where a long night ends. Across the harbour, Kowloon swaps cocktails for beer and karaoke. Big clubs are scarce and every round costs a lot.

In Kaohsiung the meal is the night out. At a stir-fry hall you keep ordering dishes to go with the beer and stay at the table for hours, then perhaps move on to a riverside terrace or a craft beer bar near Pier-2. The mood is easy and mostly local, but on a weeknight there is little else, and anyone who wants to dance has to wait for the weekend clubs of Sinsing and Lingya.

Hong Kong has the more dramatic outdoors, with wild hills rising straight behind the towers. The Dragon's Back ridge, a sunrise climb up Lantau Peak, the MacLehose Trail and the volcanic columns and sea caves of Sai Kung are all within reach by public transport.

Kaohsiung's nature is gentler and more spread out. In the city there is Shoushan, a forested hill full of macaques above the harbour, plus cycle paths along the Love River. The striking landscapes, such as the Moon World badlands, the mud volcanoes and the gorges of Maolin, are an hour or two away. In both cities autumn and winter are the season for hiking.

Both cities have good day trips, but they lead in different directions. From Hong Kong you head across borders: by ferry or bridge to Macau's Portuguese squares, or by fast train to Guangzhou and Shenzhen, which means checking visa rules first. Closer to home, the car-free outlying islands make easy outings.

Kaohsiung's trips stay inside Taiwan and need no paperwork. Tainan, with its forts, temples and food, is half an hour away by high-speed rail. Fo Guang Shan's giant Buddha, the Hakka town of Meinong and the Alishan tea country via Chiayi are all within easy reach.

Children will find bigger days out in Hong Kong. Disneyland and Ocean Park, with its pandas and aquarium, are the headline outings, and the Peak Tram, the Star Ferry and the Ngong Ping cable car are treats in themselves. The drawbacks are weekend crowds, sticky summers and hotel rooms that leave little space for a family.

Kaohsiung is warm towards children but has fewer big attractions. The hands-on science museum, the Dashu theme park and the short ferry to Cijin fill a few days. Pavements blocked by scooters and busy junctions mean holding small hands more tightly.

Hong Kong is one of the easiest cities anywhere to get around. The MTR reaches almost everywhere, from the airport to the New Territories, and the Star Ferry, the trams, covered walkways and the Mid-Levels escalator make the short hops between sights almost effortless.

Kaohsiung's red and orange metro lines and its harbour light rail are clean and clearly signed, but the network is thin for such a spread-out city. You will often finish a journey by bus, taxi or bike-share, and walking means stepping around parked scooters in the heat.

Hong Kong is a shopping city in its own right. Luxury flagships line Central and Canton Road, the malls carry every international brand with no sales tax, and the Ladies' Market, the goldfish and flower markets, Sham Shui Po's fabric lanes and the curio shops of Hollywood Road are worth seeing even if you buy nothing.

Kaohsiung mostly shops in Japanese-style department stores and a large harbourside mall, with youth fashion in the streets of Xinjuegang. The things to take home are tea, pineapple cakes and dried mullet roe, and there is little in the way of luxury or independent boutiques.

Kaohsiung is by far the cheaper of the two. Market meals, night-market snacks, low transport fares and fairly priced business hotels keep costs down, and most temples, parks and Pier-2 are free.

Hong Kong's main problem is where you sleep. Rooms are among the dearest in Asia and often tiny, and a harbour-view dinner or a cocktail in Central costs as much as in London or New York. Noodle shops, cheap ferries and free hiking trails soften the bill, but they cannot close the gap.

The two are about level, and both rely on touring shows and theatre in the local language. Hong Kong has the Hong Kong Philharmonic at the Cultural Centre, the annual Arts Festival, a few jazz bars in Central and Sheung Wan, and Cantonese opera with its painted faces at the Xiqu Centre and in village bamboo theatres.

Kaohsiung's showpiece is Weiwuying, a vast wave-roofed arts centre with an opera house, a concert hall and a playhouse. Mandarin pop fills the harbourside Music Center and the Arena, and glove puppetry and Taiwanese opera still turn up at temple festivals.

Neither city is built for rest, and both rely on massage rather than bathing: foot reflexology parlours sit on ordinary streets in both. Hong Kong adds traditional Chinese medicine, herbal tea shops and some very polished hotel spas, but for calm you have to leave the crowds behind for Chi Lin Nunnery or car-free Lamma.

Kaohsiung's slower pace does more of the work. An evening by the Love River or Chengcing Lake is restful in itself, though the nearest hot springs at Baolai are far enough away to need an overnight stay.