Narrower car lanes: lessons from 10 days of driving in Thailand

On my most recent trip to Thailand, I rented a car and drove for nearly 10 days. With almost a decade of experience behind the wheel in Hanoi and across Vietnam, driving there was not difficult.

But there was an obvious difference: the lanes are indeed small. In many places, a lane is only as wide as a single car. If two cars stop side by side, the remaining gap is just enough for a motorbike to pass. If you don't keep your car neatly aligned, a slight steering input can put you into the next lane.

This geometry encourages discipline. In Bangkok, cars form tidy queues. On expressways, the benefit is capacity: more, narrower lanes instead of fewer, wider ones. Driving from the airport to the center, I counted five lanes plus an emergency lane. Rather than three or four cars drifting across overly wide lanes, five streams of traffic moved briskly within compact ones.

Cars line up neatly in three lanes on a road in Bangkok. Photo by Choc Cheo

What does it feel like to drive in narrow lanes? At first, it demands focus. For two or three days I found it slightly stressful because it's easy to hit the lane line. Then it became comfortable. Thai drivers, in my experience, travel quickly and straight within their lanes, signal and change lanes decisively, often in two clear moves, and, notably, they don't lean on the horn.

I took that lesson to heart: I didn't honk for the entire 10 days, and everything was fine. On Hanoi's Vo Chi Cong Street, by contrast, cars often fail to line up tightly, leaving wasted space, even when most vehicles keep to their correct lane without encroaching or breaking rules.

People ask whether larger vehicles can manage in narrower lanes. Trucks and buses do, routinely.

These lane widths are only one part of a broader traffic toolkit I've seen in neighboring countries. Pavement markings, signposting, road surface symbols—others have deployed them extensively and for years. My first visit to South Korea left me thinking, "They paint so many instructions on the road"—and not just many, but clear and colorful ones. Yielding to pedestrians in the correct lane is treated as a given.

In China, "no horn" signs are ubiquitous and cameras are dense. The payoff is quiet streets; I stayed at a hotel right by an intersection and hardly heard a honk.

From what I've seen, narrower, well-marked lanes can increase throughput, encourage orderly driving, and reduce noise—provided they're paired with clear signage, consistent enforcement, and a culture of lane discipline.