From London you can fly from Heathrow or Gatwick to Phnom Penh International Airport. Once you have arrived, taxi, moto or tuk-tuk wil get you into Central Phnom Penh. By taxi it’ll cost between $9-$12 depending on where in Phnom Penh you are going and will take between 25 and 50 mins. Tuk tuk will cost $5-$7 and moto just $2 but these are only available outside the airport gates.
The journey from Bangkok to Siem Reap is a popular one for backpackers, but its plagued with rip-offs and hassles. This is one route where it pays to be wary of cheap deals. While you won’t find yourself dumped in the middle of nowhere if your ticket you got in Bangkok isn’t all it was supposed to be, you might find yourself being dropped just inside the Cambodian border having to join with other travellers to hire a car to Siem Reap.
Bangkok Airways & Siem Reap Airways have all the domestic routes between them mainly now between Phnom Penh and Siem Reap.
Buses link most of the bigger cities and are reasonably priced. A bus ride from Phnom Penh to Siem Reap will cost around $5.
The train service in Cambodia was virtually non-existant over recent years however a regular service has been re-introduced between Phnom Penh & Sihanoukville stopping at Takeo & Kampot. The journey costs around $6.
Taking a boat trip between Phnom Penh and Siem Reap was once the best way of getting between the two cities. But the bus is now quicker and cheaper, and low water levels at many times of the year mean the trip is a real hassle. You can also take a boat between Battambang and Siem Reap but the trip is plagued by same problems with low water levels.
If you want to explore Cambodia’s outlying areas, your best bet will be to hire a four-wheel drive, and a driver and guide.