Bangkok–Chiang Mai Sleeper

First, the thing that will otherwise ruin your evening: the train does not leave from Hua Lamphong.

Since January 2023, Thailand's long-distance trains have departed from Krung Thep Aphiwat Central Terminal, out at Bang Sue — an enormous new station well north of the old one. Hua Lamphong, the beautiful domed terminus in the middle of Bangkok that appears in every photograph ever taken of Thai railways, now handles ordinary and commuter trains only. A great deal of travel writing has not caught up. Anyone who arrives at the wrong one will not be catching a sleeper.

With that out of the way: this is one of the world's great overnight trains, and it is absurdly cheap.

The Northern Line runs 751 kilometres from Bangkok to Chiang Mai on metre-gauge track, and it took a very long time to arrive. The first stretch, Bangkok to Ayutthaya, opened on 26 March 1896. The rails did not reach Chiang Mai until 1 January 1922 — twenty-six years, because of what sits in the way.

What sits in the way is the Khun Tan Tunnel.

It is the longest railway tunnel in Thailand, about 1,352 metres, and it took eleven years to dig — from 1907 to 1918. The man who drove it was a German engineer named Emil Eisenhofer. It nearly broke him and it did break a great many other people: over a thousand workers died in that mountain, from accidents, from suffocation, from malaria, from tigers, and from fighting each other. Work stopped partway through when Thailand entered the First World War and the German engineers were arrested.

And here is the part that stays with you. Eisenhofer went home. Then he came back — he returned to Thailand later in life and died here in 1962, forty-four years after the tunnel was finished. His ashes are in a memorial at the tunnel's mouth, because he wanted to rest where he had worked. The monument honours him and the workers who died alongside him.

Your train goes through their tunnel in the dark before dawn, in about a minute, and almost everyone aboard is asleep.

So the night train it is: a lower berth, dinner in the dining car, the hills folding in around Lampang as you wake, and Chiang Mai for breakfast. But somewhere near the end, when the noise closes up and the windows go black for a minute, it is worth being awake.

Krung Thep Aphiwat is not a romantic place. It is vast, air-conditioned, clean and slightly bewildering, and it feels like an airport that has mislaid its aeroplanes. Give yourself time; the platforms are a walk.

Then you find your carriage, and it is fine — better than fine. Trains 9 and 10 run the newest Chinese-built sleeping cars, with power sockets and information screens, in first class and second class air-conditioned. Second class is the one to have: an open carriage of facing seats, wide windows, and a corridor down one side.

18:40, and out through the Bangkok suburbs while the light goes.

The first hours are the central plains — flat, wet, green, endlessly worked. Ayutthaya goes by in the dusk, and if you have any sense you are in the dining car by now, because the dining car on a Thai sleeper is one of the small perfect things in travel: fluorescent-lit, rattling, serving decent food and cold beer to a carriage of people who are all quietly delighted with themselves.

Somewhere north of there the attendant works down the carriage folding the seats into beds. Sheets, a blanket, a curtain, a little reading light. Book a lower berth — it costs slightly more, it has the window, and you can lie there and watch the level crossings go past.

The line climbs overnight, through Phitsanulok and Den Chai and up into the hills around Lampang. And then, in the dark, it reaches Khun Tan.

The station is the highest in Thailand, at 578 metres. Beside it is the tunnel — 1,352 metres, eleven years, a thousand dead, and Eisenhofer's ashes in a memorial at the portal, which you will not see because it is still dark. The train goes in. The sound closes up, the windows go black, and about a minute later you are out the other side and into Lamphun province. It is the most significant minute of the journey and the entire train sleeps through it.

Curiously, the tunnel is bigger than it needs to be. It was bored for standard gauge before the line was regauged to a metre, so the train runs through a hole cut for a larger railway that never came.

You wake up somewhere in the last hour, and this is the reward. The plains have gone. The country is folded and green and full of mist sitting in the valleys, the train is working along the side of the hills, and the light is the pale gold you only get at that hour. Coffee. Eggs, if you want them.

Chiang Mai at 07:15, with the whole day in front of you and a night's sleep behind — which is the entire argument for a sleeper, and this one makes it better than almost anywhere.

There are three overnight sleepers a night, and they all leave from Krung Thep Aphiwat Central Terminal — not Hua Lamphong.

How they run:

Good to know:

• The station moved in January 2023. Long-distance trains go from Krung Thep Aphiwat (Bang Sue). Hua Lamphong keeps ordinary and commuter services. This is the single most common way to get this trip wrong.
• No. 9 is the one. It has the newest Chinese-built (CNR) sleeping cars — power sockets, information screens, properly made-up berths — and it lands you in Chiang Mai at a civilised 07:15 with the whole day ahead.
• No. 51 trades sleep for scenery. Arriving at 11:40 means you spend the whole morning in the northern hills in daylight, which is the prettiest part of the line. If you don't need the day at the far end, it is a real option.
• Lower berths are worth it. They're wider, they have the window, and they cost only a little more. Uppers are fine, but you're sleeping in a shelf with no view.
• Both directions are overnight. Coming back, the same trains run Chiang Mai to Bangkok on a mirrored schedule.
• Book as far ahead as you can. The modern sleepers are popular and the good berths go first — especially over Thai holidays and in the November-to-February high season.
• Khun Tan is a real station. If you want the tunnel, the memorial and Doi Khun Tan National Park, you can get off there. You'll need a day train to do it in daylight.

Tickets come from the State Railway of Thailand, and this is one of the best-value overnight trains anywhere — a bed and 751 kilometres for less than a cheap hotel room. Nearly everyone should book a 2nd class air-conditioned sleeper: an open carriage of berths behind curtains, made up by the attendant in the evening, and on trains 9 and 10 these are the new Chinese-built cars. First class is a two-berth cabin with a door, worth it as a pair and not worth it alone.

Within second class the choice that matters is the berth: the lower is wider, has the window and costs a little more. Book at dticket.railway.co.th (opens in a new tab), SRT's own system — cheapest but not friendliest. Bring a layer, because the air conditioning is genuinely cold, and go to Krung Thep Aphiwat, not Hua Lamphong.

The line's stops are worth breaking the journey for — and almost nobody does, which is their loss. The sleeper makes it easy to treat the route as a series of towns rather than one overnight hop: get off, spend a day, pick up the next train north.

Den Chai is the station for Phrae, a quiet old teak town most visitors have never heard of, with the best surviving teak mansions in the north — and no reason at all to be as overlooked as it is.

The train is the hotel — that's most of its appeal. You go to bed in Bangkok and get up in Chiang Mai, and you have paid for the night once.

Your berth is the whole decision. A lower berth in 2nd class air-conditioned is the sweet spot: wide enough, curtained, made up properly, with the window beside you. 1st class buys a two-berth cabin with a door, which is worth it for a couple and pointless alone. Bring a layer — the air conditioning is fierce — and an eye mask if you're fussy, because the carriage lights stay dim rather than off.

At either end:

• Bangkok — stay wherever you like, but understand that Krung Thep Aphiwat is out at Bang Sue, not in the centre. It's on the MRT, which is the sane way to reach it; allow more time than feels necessary, and don't rely on a taxi in the evening traffic.
• Chiang Mai — arriving at 07:15 means you land before check-in almost anywhere. Either book the previous night so the room is yours on arrival, or pick somewhere that will hold your bag and feed you breakfast while you wait. The old city is a few minutes from the station.

If you want to break the journey rather than sleep through it, the two places worth a night are Lampang — teak temples, horse carriages, almost no tourists — and Khun Tan, where the national park has simple bungalows and campsites right by the tunnel. Waking up at the highest station in Thailand, walking down to Eisenhofer's memorial before the day trippers exist, and catching a later train on to Chiang Mai is a considerably better trip than sleeping straight through it. It costs you a day. It's worth the day.