Beware of the border crossing at Poipet. There is a scam to tell you that Cambodia no longer uses the dollar and to get you to change your money into Reils for dodgy exchange rates. It is not true. Also there are ATMs in Siem Reap, Phnom Penh and a few other places.
A one-day pass is sufficient enough time to visit some of the key temples in this beautiful enclosure. Make sure that you arrive early - sunrise is a very recommended time (go to the Bayon wat), though for the more relaxed traveller a seven/eight o’clock start will ensure that you will not only see most of the site but also without the hordes of people that arrive around eleven o’clock. Hire a tuk-tuk driver for the day, should cost no more than $10, many can speak English and some have great knowledge of the site or hire a guide. Be a bit wary of some of the freelance guides in the major wats, who’ll approach you - say one thing about a wat then expect a few dollars.
If you arrive at Siem Reap by bus, you will be 'greeted' by wave after wave of moto drivers, all offering rides to guest houses for 500 riel. There was a security guy keeping them at bay with a stick when my bus arrived! Beware - the price seems far too cheap, and it is. Once they've got you on the bike, they'll give you the hard sell to get you to hire them to be your guide around the Angkor temples etc. It's better to negotiate a realistic price with them (around 4000 riel) and then choose your guide yourself once you've checked into your hotel and freshened up etc. Much better than trying to negotiate while screaming along Siem Reap's streets on the back of a bike!
Siem Reap, bus station
Unless you are flying in or out of Bangkok / Phnom Penh, due to Cambodia's primitive infrastructure getting to Siem Reap can be a nightmare.
If you are determined to travel overland, it's worth checking out the website below. The author is clearly an old Cambodia hand and his site is filled with regularly updated info, tricks and tips on how to get around.
And loads of other nice stuff on the rest of the site.
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