Bangkok or Phnom Penh?

Neither city has a beach, and in both you swim in a hotel pool. Bangkok is slightly better placed, because Bang Saen and Pattaya are close enough for a long day out by road.

From Phnom Penh, the nearest coast at Kep and Kampot is about three hours away, so sand means planning a separate stay rather than a day out.

Bangkok is the stronger food city by a long way. Thai cooking is everywhere, at every hour: boat noodles, som tam and shophouse curries, Chinatown's night-time kitchens and Banglamphu's grazing streets. Above that sits a deep layer of serious restaurants, cocktail bars and specialist coffee.

Phnom Penh's Khmer cooking is gentler and more herbal, with dishes such as amok, lok lak and bai sach chrouk at the morning markets, and the French period left good baguettes and a café habit. It is satisfying at street level, but it has less range at the top and far fewer international kitchens.

Bangkok has the more spectacular set of sights. The Grand Palace, Wat Pho and Wat Arun are joined by dozens of working temples and Thonburi's canal-side houses, enough for several days around Rattanakosin and the river.

Phnom Penh's sights are fewer and closer together, but they carry real weight. The Silver Pagoda and the National Museum's Angkorian sculpture sit by the riverfront, and Tuol Sleng and Choeung Ek face the Khmer Rouge years head on. Two or three days covers them.

Bangkok's nightlife is far bigger and comes in several distinct scenes. There are polished cocktail bars and clubs in Thonglor and Ekkamai, the backpacker street party on Khao San, Silom's gay scene and the rooftop bars above the skyline.

Phnom Penh's night out is looser and smaller, packed into a few blocks around Bassac Lane, the riverside and Street 51, where late bars keep going into the early morning. It has character, but you will see most of it in a night or two, and you need to watch for bag snatching from passing motorbikes.

Both are flat, hot river cities where outdoor life is modest, and the best green escapes are similar in kind. In Bangkok you cycle the raised paths of Bang Krachao or watch monitor lizards in Lumphini Park. In Phnom Penh you take the ferry to Koh Dach, cycle past stilt houses, or watch the sunset from a boat where the rivers meet.

For real landscape, Bangkok has Khao Yai's forests and elephants and the Kanchanaburi hills, while Phnom Penh has the pine plateau of Kirirom. In both cases you need an overnight stay rather than a day.

Bangkok gives you much more to do in a day. Ayutthaya's ruined capital alone fills one, and the canal country to the west adds the Amphawa and Maeklong railway markets, with Kanchanaburi's Death Railway bridge as a longer outing.

Phnom Penh's days out are quieter and smaller in scale: the stupas of Oudong, the lakeside temple at Tonle Bati, Phnom Chisor on its hilltop and the silk-weaving villages on the Mekong islands. They are pleasant, but Angkor and the coast are too far to reach in a day.

Both cities make a fuss of children, but Bangkok gives families much more to work with. It has places built for them, from the aquarium under Siam Paragon to Dream World and KidZania, and the Skytrain makes short, cool hops easy.

In Phnom Penh, the missing pavements, constant motorbikes and sights unsuitable for children make the days harder. Phnom Tamao, river cruises and the mall play areas cover only part of a stay, so it suits families already used to travelling in the region.

Bangkok has rails and Phnom Penh does not, and that is the main difference. The Skytrain, the MRT and the Chao Phraya boats link most areas a visitor needs, though the old city and rush-hour roads are slow.

Phnom Penh relies on tuk-tuks and motorbike taxis, made easier by ride-hailing apps, with its main sights close together by the river. Walking is hard going in both cities.

Bangkok is a real shopping destination. Chatuchak's weekend market alone fills a morning, and the malls of Siam and Ratchaprasong run from luxury floors to MBK's bargains, with Pratunam and the night markets on top.

Phnom Penh is about markets and crafts rather than fashion. You can find silver, carvings and overrun clothing at the Russian Market, and silk, Kampot pepper and cooperative-made homeware in the boutiques around Street 240.

Both are very easy on a budget, and both get expensive in the same places: imported wine, Western restaurants and international hotels. Bangkok adds a sizeable entry fee at the Grand Palace and global prices at its rooftop bars.

Phnom Penh keeps sight fees modest and boutique hotels with pools good value, so how much you spend in either city depends mostly on how often you eat local food.

Bangkok has more to see on stage. Khon masked drama is staged at the Sala Chalermkrung and the National Theatre, there is a symphony orchestra at the Thailand Cultural Centre, and Muay Thai nights at Rajadamnern and Lumpinee come with their own ritual music.

Phnom Penh's great offering is classical Khmer dance, rebuilt after the Khmer Rouge years and performed in evening shows with shadow puppetry near the National Museum. Beyond that, there are only a few jazz and acoustic bars.

Bangkok is the better place for pampering. Wat Pho still teaches traditional Thai massage, street parlours stay open late, and the grand hotels run some of Asia's finest spas.

Phnom Penh has massage on every street too, including blind-masseur centres and NGO spas, and a villa hotel on a leafy street can feel quieter than anywhere in Bangkok. The choice of spas is much smaller, though.