If you are planning a trip to Thailand you might consider renting a car and driving yourself around from place to place. I have done that and if you plan to as well, let me give you the basic rules of the road and some advice based on my personal experiences.
The first time I rented a car I was in a small village on the island of Koh Samui. Pretty easy to drive around there as the roads are not crowded at all as long as you are away from the airport. Even in the area surrounding the airport not really too much traffic to be seen.
The biggest issue I had the first time I rented a car was learning to drive on the left side of the road. I guess you could also call my grinding the gears a problem as well. It was a challenge for me to shift with my left hand, now I know how it is that there are so few Americans driving in Formula 1! If however you are from the UK you should have no trouble at all.
Thailand has a good network of well-maintained roads and highways between all main centers. Road signage follows international convention and most are in both Thai and English. Drunk drivers and an abundance of haphazardly driven motorcycles can make night-time driving a real problem. I normally try to get where I am going well before the sun drops.
Traffic drives on the left hand side and drivers must be at least 18 and hold a full, valid Thailand driving license or an international driving permit. If you only have a national driving license from your own country you will be permitted to use for up to two months. To hire a car, renters have to be at least 25 years old. Wearing of seat belts is compulsory and drunk-driving laws apply; all insurance is invalid if drivers exceed the legal alcohol limit.
Police occasionally set up speed traps and offenders breaking the limits will be subject to on-the-spot fines, which are routinely less than the official rate, but no ‘ticket’ is given. The maximum blood/alcohol limit is 0.5mg/ml. unfortunately the Thai police are very lax in controlling drunk drivers and this creates a hazard late at night.
Urban areas: 45 – 60kph/28 – 37mph
Highways: 90 – 110kph/56 – 68mph.
Motorways and the road network
There are about 64,600kms/40,141miles of paved roads in Thailand as well as a large network of unpaved roads (especially in the North). Major highways radiate outwards from Bangkok to all the major cities, with most of the north-south route consisting of divided freeways. Interconnecting roads to smaller towns and cities are usually wide, and single-lane with two-lane sections at interchanges and close to any town or village.
Parking in cities is usually on the street for a small charge or, for the most part, covered parking in hotel/plazas or shopping centers. Farther out of town centers parking is usually free, if you can find a space. Like any place else be sure not to park near government buildings or police departments as you will be towed.
Renters requiring assistance will find an emergency phone number printed on their rental agreement and on the windscreen sticker. Try to refrain from driving at night as unsuspecting potholes, local drivers without tail lights and wandering livestock can greatly increase the possibility of having an accident.
In my experience Thai drivers take the rules of the road pretty loosely. They seem to make lanes more fluid than fixed, seem to enjoy just wondering around the road and taking the smallest opening as a challenge to be met head on.
When you are in Bangkok, do yourself a favor and just catch a bus, taxi or Tuk Tuk. There is also a lot of road rage in BKK. There is much disregard for other drivers. If you do choose to drive there, stay toward the center of the road as taxis and little mini bus trucks to stop often and without warning.
But above all have a great time, watch what you are doing carefully, and have a great trip!