Thailand in 7 Days — Bangkok–Chiang Mai–Ayutthaya, Day by Day

Land at Suvarnabhumi or Don Muang, head into the city and drop your bags first. Don't cram the first day — your body's still tired. Start gently in the evening at Yaowarat, the Chinatown road that turns into a street-food heaven after dark: noodles, charcoal-grilled seafood, Chinese sweets. Graze your way along it and ease into the rhythm of the city before a full day tomorrow.

Today's for the three big temples clustered by the river. Start early at the Grand Palace and Wat Phra Kaew to beat the midday heat and the crowds, walk on to Wat Pho for the giant Reclining Buddha, then take the cross-river ferry to Wat Arun, finishing with its riverside spire in the soft evening light.

Your last day in Bangkok for now — take your pick. Market people head to Chatuchak (if it's a weekend); for modern Bangkok, browse the malls around Siam or riverside ICONSIAM. Have a good lunch, then in the evening go to Krung Thep Aphiwat Central Terminal and board the sleeper train heading north to Chiang Mai. Sleep on board, wake up there, and save a night's hotel.

The train arrives in Chiang Mai this morning; drop your bags at a hotel in the old city and start walking inside the square moat. Take in Wat Chedi Luang, with its huge ancient chedi, and Wat Phra Singh, a gem of Lanna craftsmanship. In the afternoon, head up the mountain to Wat Phra That Doi Suthep for the golden stupa and a view over the whole city.

This morning, visit an ethical elephant sanctuary with no riding and no shows — you feed the elephants, walk alongside them, and watch them live in a natural setting; pick a place that genuinely cares for its animals. In the afternoon, head back into town for the walking street (if it falls on a weekend) to browse crafts and northern food, then catch an evening flight back to Bangkok.

Today, take the train or a van from Bangkok to Ayutthaya, the former royal capital that left brick temple ruins scattered across the island city. See Wat Mahathat, with its famous Buddha head wrapped in tree roots, Wat Chaiwatthanaram, lovely by the river in the evening light, and Wat Phra Si Sanphet, with its three chedis in a row. Rent a bicycle or hire a tuk-tuk to loop the sites in a single day.

The last day flexes around your flight time. If you fly out in the afternoon or evening, there's still time for shopping — souvenirs around Siam or a market — and to catch whatever you missed: a riverside floating market, a park, or a farewell meal by the water. If you haven't had your fill of street food, today's the day to fix that, before taking the Airport Rail Link or a Grab to the airport.