There are 11 countries in Southeast Asia, and much of the region is pockmarked with islands although most of it can be toured overland which is more fun than flying. The main overland routes are between Thailand and Malaysia while Thailand and Laos, Vietnam and Cambodia are also well connected by road.
By Train: Thailand has the most useful railway system for tourists with main lines going off in all directions from Bangkok. In general, however, rail travel in Southeast Asia is slow and vehicles poorly maintained. The advent of budget airlines in Southeast Asia has made rail travel less attractive.
The Bangkok to Singapore route is the most reliable and useful train route in the region, taking in major Malay cities such as Johor Bahru, Malacca, Kuala Lumpur, and Butterworth. Total journey time is a little over 41 hours and, although considerably longer than traveling by plane, takes in many popular destinations. The upmarket Oriental Express also runs this route.
Reliable rail services also run along the Vietnamese coast from south to north and north into China, while Cambodia, Indonesia and Burma (Myanmar) have limited and often decrepit services.
By Bus: Bus travel is the cheapest and most extensive overland option for getting around in Southeast Asia. Services range from slow, budget to express VIP air-conditioned vehicles in Thailand, Malaysia and Singapore. Services generally run hourly to and from major cities. Indonesia, Vietnam, and the Philippines also have reliable bus services yet traveling by bus in Laos and Cambodia can be arduous.
By Car: Car rental in Southeast Asia is inexpensive and can be done independently in Thailand, Malaysia and Singapore without too much fuss. If you intend on seeing the likes of Vietnam, Laos, or Indonesia by hire car, try and rent a vehicle with a driver. Road rules can be strange in Southeast Asian climes and you will find that many countries will not allow you to take hired cars across borders.
By Air: With the profusion of low-cost air carriers in Southeast Asia, most people tend to get about by plane if they have little time and/or don’t like traveling overland. The main air hubs in the region are Bangkok, Kuala Lumpur and Singapore. There are also international airports in Chiang Mai, Phuket, and Koh Samui in Thailand as well as Penang and Langkawi in Malaysia and Ho Chi Minh City and Hanoi in Vietnam. You can also fly into Siam Reap in Cambodia to access Angkor Wat or into Luang Prabang and Vientiane in Laos.
By Boat: Getting around by boat is the chief form of public transport for large swathes of Southeast Asia including the Philippines and Indonesia with their 20-odd thousand islands. The Mekong River is also a popular travel artery allowing for access in north-eastern parts of Thailand, Laos and Vietnam.