🔄 Updated 7 Jul 2026
The short version: fly into Bangkok, give it 3 days plus an easy Ayutthaya day trip. Head to the north for a full week — Chiang Mai's temples and cooking classes, the mountain road to Pai, and quieter Chiang Rai. Then take one short flight south for the Andaman islands, and finish on a second beach or the Gulf. Because you're not counting hours, you can add a rest day, a multi-day cooking course, or a scuba certification. Want to trim or reshape it? See the alternative routes below.
The 3-week route at a glance
| Days | Base | Highlights | Get there |
|---|---|---|---|
| 1–4 | Bangkok | Grand Palace & Wat Pho, Chinatown, markets, an Ayutthaya day trip | Fly into BKK/DMK |
| 5–7 | Chiang Mai | Old-town temples, elephant sanctuary, cooking class, Doi Suthep | 1-hr flight or sleeper train |
| 8–9 | Pai | Mountain road, hot springs, waterfalls, slow café days | 3-hr minivan from Chiang Mai |
| 10–11 | Chiang Rai | White Temple, Blue Temple, tea hills, night bazaar | Bus/van, or fly back via Chiang Mai |
| 12–15 | Krabi & Andaman | Railay, Phi Phi, Koh Lanta, island-hopping, a dive day | Fly south (via Bangkok) |
| 16–21 | Second island / Gulf | Rest, a dive certification, or a change of coast | Ferry or short flight |
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Plan my trip →Days 1–4: Bangkok & Ayutthaya
Start where almost everyone lands. With three weeks ahead you don't need to blitz Bangkok — spread it out, temples in the cool mornings, a river boat, street food at night, and one easy day out to the old capital. Base near the BTS/MRT (Sukhumvit or Silom) so the traffic never wins.
- Day 1: ease in after the flight — a riverside temple or two, then Chinatown (Yaowarat) for street food after dark
- Day 2: the big hitters — Grand Palace, Wat Pho's reclining Buddha, Wat Arun across the river; a rooftop bar at sunset. See the Grand Palace & temples guide
- Day 3: a market morning (Chatuchak on weekends, or a floating/train market), cafés and shopping — a deliberately slow day
- Day 4: the easy day trip to Ayutthaya, cycling between brick temples and stone Buddhas. See Bangkok to Ayutthaya
Where to stay in Bangkok
Stay near a BTS or MRT station to skip the traffic. Our ranked pick of the best-value hotels, verified from real guest reviews:
See Bangkok hotels →Days 5–11: the North (Chiang Mai, Pai, Chiang Rai)
A one-hour flight — or a scenic overnight sleeper train — lands you in a cooler, greener Thailand: moated old towns, hundreds of temples, mountains on every side. Give the north a full week and it earns it. See how to get from Bangkok to Chiang Mai (flight vs sleeper train).
- Days 5–7 · Chiang Mai: old-town temples on foot, sunset at Doi Suthep, a morning at an ethical elephant sanctuary (no-riding, observation-first), and a hands-on Thai cooking class. Tickets on the Chiang Mai attractions page
- Days 8–9 · Pai: the winding mountain road up (762 curves), then hot springs, waterfalls and lazy café mornings. See Chiang Mai to Pai for the minivan vs motorbike call
- Days 10–11 · Chiang Rai: the White Temple, the Blue Temple and tea-covered hills; quieter than Chiang Mai and worth the detour. Deciding between the two? Read Chiang Mai vs Chiang Rai
Where to stay in Chiang Mai
The old town puts you walking distance from the temples, markets and cafés — your base for the whole northern week.
See Chiang Mai hotels →Days 12–15: Krabi & the Andaman islands
Fly south (usually via a quick Bangkok connection) and swap mountains for limestone cliffs dropping straight into turquoise water. Base in Ao Nang or Railay and give yourself four days of beaches and boats — enough to island-hop and still have a slow day. See the Krabi tours & tickets and our island-hopping guide.
- Day 12: arrive, settle into Ao Nang or take the longtail to car-free Railay for cliffs and calm beaches
- Day 13: the classic island-hopping day — Phi Phi, the Hong Islands or the 4-Islands tour by speedboat. Coming from Phuket instead? See Phuket to Phi Phi
- Day 14: ferry down to laid-back Koh Lanta for long, quiet beaches and sunset bars
- Day 15: a dive or snorkel day off Lanta (Koh Haa, Hin Daeng) — or just a beach and a book
Where to stay in Krabi
Ao Nang for restaurants and ferry access; Railay for cliffs and quiet.
See Krabi hotels →Book the highlights of this route
The experiences three weeks gives you room for — compare options and reviews:
Days 16–21: a second island, the Gulf, or a dive cert
The last six days are yours to shape. This is where three weeks pays off: instead of racing home, you can change coasts, plant yourself on one beach, or use the time to earn a scuba certification. Here's how to spend them without rushing.
| You want | Suggested plan | Good to know |
|---|---|---|
| A change of coast | Fly/ferry to the Gulf: Koh Samui + Koh Phangan | Often drier in May–Oct; see Samui vs Phangan |
| To learn to dive | Base on Koh Tao for a 3–4 day open-water course | Cheapest, calmest place in Thailand to certify |
| Pure rest | One island, no plans — Lanta, Koh Yao Noi or Phangan | Build in a genuine do-nothing day or two |
| Only have 2 weeks | Drop Chiang Rai + the second island | See our 2-week and 10-day itineraries |
🏝️ Koh Samui vs Koh Phangan
Pick your Gulf island
🤿 Diving in Thailand
Where to learn and dive
⛴️ Thailand island hopping
Andaman vs Gulf, which islands
🚌 Getting around Thailand
Flights, trains, ferries, Grab
💡 Know before you go (for this route)
Bangkok–Chiang Mai and the north–south hop are cheap booked weeks ahead. Overland the north (Chiang Mai–Pai–Chiang Rai) by minivan and bus; save flying for the long jump south.
Most nationalities get 30–60 days visa-free, which covers three weeks comfortably — but confirm your allowance before you book. See our visa guide.
Cool, dry season is ideal countrywide. In the north, Feb–Apr can bring burning-season haze; check air quality if that's your window.
If you travel May–Oct, the Gulf islands (Samui, Phangan, Tao) often stay drier than Krabi/Lanta. Flip the beach legs accordingly.
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