Ayutthaya or Pattaya?

Pattaya wins this easily. Ayutthaya sits on an inland river plain with no beaches, and its rivers are working waterways, so swimming means the hotel pool.

Pattaya has a warm sea all year, though the water off the central beach is cloudy and full of jet skis. Jomtien is the better place for a swim, and for clear water and pale sand the ferry out to Koh Larn is the real draw.

Both are at their best with Thai food at local prices, but Pattaya has the wider range, and its seafood, grilled and sold by weight along the Naklua waterfront, gives it the edge. It also has plenty of international food for anyone tired of curry, though much of that is uneven tourist fare.

Ayutthaya's cooking is narrower and more provincial, but it has specialities of its own: boat noodles eaten several bowls at a time, giant river prawns and the spun-sugar pancakes called roti sai mai. Beyond Thai food there is very little.

This is where Ayutthaya pulls far ahead. Four centuries as the capital of Siam left a whole island of ruined temples, from the three chedis of Wat Phra Si Sanphet to sunset at Wat Chaiwatthanaram. It also has a national museum of crypt gold and the remains of the Portuguese and Japanese quarters.

Pattaya began as a fishing village that became a resort, and it has little history to show. The Sanctuary of Truth is genuinely striking and Big Buddha Hill adds a view over the bay, but most of what remains is illusion galleries and wax museums.

Pattaya's nights are what it is known for: the clubs and live-band bars of Walking Street, hundreds of beer bars off Second Road, rooftop bars and a gay quarter, all running late. Much of it is tied to the sex trade, and quieter evenings are easier to find in Jomtien or Naklua.

Ayutthaya has a short strip of backpacker bars and a few riverside terraces where you can drink facing the lit-up ruins, and most visitors are in bed well before midnight.

Neither is a place for wild landscape, but the sea gives Pattaya more to do outdoors. Boats go out to snorkel around Koh Larn and the nearby islands, dive trips visit coral and sunken naval ships, and Na Jomtien is good for kitesurfing in the dry season.

Ayutthaya's outdoors is flat and gentle: cycling past rice paddies, watching egrets and circling the island by long-tail boat. For forest, both depend on a drive, to Khao Yai from Ayutthaya or to the closer Khao Kheow hills from Pattaya.

Ayutthaya has the better spread of outings. Bangkok is closer and an easy train ride away, the royal palace at Bang Pa-In is only twenty minutes off, and Lopburi offers Khmer temples and its monkeys.

From Pattaya, Bangkok is a longer road trip that depends on the traffic. Its other outings are coastal instead: the old royal summer palace on Koh Si Chang, reached from Si Racha, and the white beaches of Koh Samet about two hours away.

Pattaya is the easier place with children. Water parks, an aquarium with a walk-through tunnel and the night safari at Khao Kheow zoo can fill several days, as long as you stay in Jomtien or at a resort away from the bar streets.

Ayutthaya keeps young children interested for a morning or so, with the Buddha head in the tree roots and space to run about the temple grounds. The ruins have little shade, though, and almost nothing is built for children.

Neither has much public transport, and in both the heat limits how far you can walk, so the difference is in what fills the gap. Ayutthaya's old city is compact and flat enough to cycle, with tuk-tuks for hire by the half-day and small ferries across the rivers.

Pattaya relies on shared songthaew pick-ups looping the coast road to Jomtien and Naklua, and on taxis and ride-hailing for everything else, including the zoo and water parks. Its broken pavements and heavy traffic make it the less pleasant of the two on foot.

Pattaya is the better place to shop, though mostly for practical things: large air-conditioned malls, night markets at Thepprasit and Jomtien, and tailors who will make a suit within days. Ayutthaya has little beyond market stalls, amulets and temple souvenirs, and its most genuine crafts are downstream at the Bang Sai centre.

Both are cheap, and Ayutthaya is cheaper still, with riverside guesthouses, noodle stalls and bicycle hire that costs next to nothing, so the main outlay is the separate entry fee at each ruin. In Pattaya, the oversupply of rooms keeps beds cheap, especially in the wet season, but speedboats, water parks, shows and imported drinks soon add up.

Pattaya has more on stage, though all of it is aimed at visitors: ladyboy cabaret in big theatres, dinner shows with Thai dance and cover bands playing until late. Ayutthaya is quieter still and comes alive mainly during its annual World Heritage fair, when light-and-sound shows retell its history among the ruins.

Massage is what the two have in common, and both have cheap shophouse parlours. Pattaya adds proper day spas and resort spas on the Pratamnak headland and in Naklua, though in the centre the noise follows you to bed and some massage places belong to the nightlife trade.

Ayutthaya has few spas but a slower pace. Once the tour buses leave, an evening on a riverside terrace is rest in itself.