A valid international driver’s license is a necessity for most visitors, while those from ASEAN countries (Association of Southeast Asian Nations) need only have a license from their home countries. International rental agencies offer safe cars and the most extensive insurance and backup services. Avis  and Budget  have desks at some airports and in major cities. Charges range from about 1,800 baht  for a day to 35,000 baht  for a month.

With other car rental companies, you should check the small print on the contract for liabilities. Insurance may not be included. Obtain a copy of the vehicle registration and carry it around with you.

Hiring an experienced driver with a car is gaining popularity in Thailand. The cost can be surprisingly low – often less than 50 percent extra on top of the normal price of car rental. Some drivers are knowledgeable about sights and will suggest interesting itineraries. Most car rental firms can arrange drivers. Siam Express  offers packages including a chauffeur, car, and accommodation in a wide range of hotels.

Mopeds and motorcycles are widely available for rent in the resorts, provincial capitals, and other large towns. In areas with a lot of guesthouses you can rent anything from a moped to a heavy-duty dirt-bike. Driver’s licenses are rarely requested, and few firms bother with insurance. Costs are low: 200 –300 baht  is average for a day’s rental. Safety precautions are essential. Check tires, oil, and brakes before you set out. Wear a helmet (compulsory in many towns) and proper shoes. Long sleeves and trousers will minimize cuts and grazes in a minor accident. Take great care on dirt roads and avoid driving alone in rural areas. Bear in mind that medical help is not always easily available.

Gas stations in Thailand are well manned and are located on main roads in towns and along highways. They are modern and most provide unleaded gas. Attendants will fill your tank, wash your windows, and pump up your tires. Some garages have a resident mechanic for bigger jobs, or will at least be able to recommend one. Most of them have a small general shop, and all have Asian toilet facilities. Many garages are open 24 hours, while others close at about 8pm. Gas itself is often cheaper than in the West.

Multistory parking lots in Bangkok are generally attached to major hotels and department stores. Parking is usually free for hotel guests, and for visitors for up to two or three hours. A ticket is issued on entry and should be stamped by a cashier; pay on the way out. Apart from these arrangements, parking can be difficult in Bangkok.

Throughout Thailand, pavements painted with red and white stripes indicate a no-parking zone. In provincial cities, many hotels and large guesthouses provide free parking facilities for guests. In quieter towns you can generally park anywhere that is not obviously going to be in the way of passing traffic.

Multilane national highways exist mostly in and around Bangkok. A toll is charged to travel on the expressways, including the one to Bangkok airport. The fee is indicated above the booth – the exact change is required at manually operated booths. The expressways are less congested than other Bangkok roads, but they are still prone to traffic jams. Many roads in Bangkok are one-way, though a lane may be reserved for buses traveling in the opposite direction.

National highways (in some places also known as routes), such as Highway 1 through the Central Plains, are fast and furious, and can be congested in places. Provincial highways are paved and vary in quality. Smaller roads linking villages are sometimes no more than dirt tracks. Main roads in towns are called thanons ; numbered lanes leading off these are called sois  and troks . In the rainy season, all roads can become flooded.

Destinations are often given in Roman as well as Thai script. Arabic numerals are always used for distances, and kilometer markers are placed along all main roads. Road markings and traffic symbols are easy to understand.

Driving is on the left. The speed limit is 60 kph (35 mph) within city limits, unless signed otherwise, and 80 kph (50 mph) on open roads. The standard international road rules apply, but are of little interest to Thai drivers. Indeed, the only consistent rule of thumb is that “size wins.”

The eccentric use of indicators and headlights can be unnerving. A left signal can indicate to another driver that it is alright to pass, while a right signal can indicate hazardous oncoming traffic, and a flash of the headlights means: “I’m coming through.”

Horns are used constantly, often as a warning of presence rather than obvious danger. Drivers think nothing of straddling lanes and passing on curves and up hill. Yield to larger vehicles at unmarked intersections. It is legal to turn left at red lights if there is a blue sign with a white left arrow, or occasionally if you are in the left lane. On minor roads, beware of roaming animals.

Traffic fines are most commonly imposed for illegal turns. If you get a ticket and your license is taken, go to the local police station, the address of which will be on the ticket, and pay the fine. Drive slowly through army checkpoints in border areas, and be prepared to stop if necessary.

Most Thais rely on mental maps and see no need for the level of cartography favored in the West. Tourist maps are widely available but cover major roads only. Some provincial, foldout maps produced by the Prannok Witthaya Map Center are excellent, showing all roads and reliefs, but are sold in few outlets. The Thailand Highways Map  by the Auto Guide Company and the Thailand Highway Map  by the Roads Association are the best atlases, and are written in Thai and Roman scripts.

In the cool season, cycling in quiet areas is a pleasant way to get around. Guesthouses and small agencies often have bicycles for rent for 20–100 baht  a day, though the bikes may be rickety. New mountain bikes may be available, but, perhaps surprisingly, costs may exceed those of mopeds. Taking plenty of water is essential and, of course, great care is always necessary on the roads.