Author John Borthwick, who writes for Adventure.com, embarks on the longest railway journey through Thailand he can find – from border to border.

The writer began his train journey in Nong Khai in northeastern Thailand to travel from Laos to Malaysia, using the longest Thai railway line he could find that crosses a border from one border to the other.

Borthwick's travel tips for trains in Thailand include booking early, especially around Thai holidays. "In sleeper cars, choose the lower berth; it's wider and a bit more expensive," he says.

Here's a short excerpt – you can read the full story on Adventure.com.

A blazing sun slowly plunges into the Mekong. For a moment, I imagine the mighty river bursting forth and drying itself up like a thermonuclear kettle.

The river lies as still as a monk. And as the sun sets, a small moon soon hangs above it in the twilight. Standing on the Thai bank, while on the other side of the water the lights of Laos come on, I ask myself: "Why should I leave?"

Arriving at a particular place and then leaving to travel somewhere else is the contradiction that accompanies most of our journeys. I came to Nong Khai in northeastern Thailand to leave from there—in this case by train and then by further trains—from Laos to Malaysia via the longest Thai railway line I could find.

Every Thai train station has a gleaming brass bell. At precisely 7:45 a.m., the stationmaster of Nong Khai steps up to his bell and rings it with a resounding blow. Train 76 lurches into motion, heading south towards Krung Thep, also known as Bangkok.

The icy air conditioning, very Thai in style, provides a pleasant coolness in this second-class carriage. But the seats are padded, quite unlike the hard, slatted benches of the uncomfortable first class I still remember. A smartly dressed conductor scans our tickets. My fellow passengers are mothers with children, couples, and a succession of snack vendors scurrying through the aisles. Shun, a Japanese traveler next to me, soon pulls his hood over his head and barely moves for the rest of the journey.

You can find the full story at Adventure.com.

All images: (c) John Borthwick