The most famous and iconic sight in the nation of Cambodia. It is also used widely as their national symbol and used on their flag. Angkor Wat lies in a huge extensive complex of temples and structures just outside of Siem Reap. Go and see the main event just before sunrise and watch the sun emerge from behind this magnificent wonder. Then you're free for the rest of the day to explore the rest. FYI everyman and his dog does this so get there even earlier if you want a front line spot but to be honest there is lots of room for everyone.
Bayon, Angkor Thom
Next stop on your tour of the temples of Angkor should be Bayon. This impressive temple at the centre of Angkor Thom is covered in 216 smiling stone faces watching you as you explore its ground. As you stroll around some will jump out at you and others you may even miss and only catch on second glace.
Most famously used in the Tomb Raider film with Angelina Jolie, Ta Prohm sits as it was found, surrounded by jungle with trees and roots growing out of it. This iconic image of ruins meeting jungle, merged as one, makes it a must visit and the prefect photo opp. Prepare to queue at peak times for popular spots though.
Temples of Angkor
The temples mentioned above are only the top few temples to see in this expansive and atmospheric complex. A day is enough if you start early - you won't have time to see everything but it is time to see enough before you're all templed out. Because it is so big you'll need transport to get you around. You can easily hire a tuk tuk for a day but cycling is also another good option to go at more of your own pace. You can also do part of it by Elephant is you so wish.
Royal Palace, Phnom Penh
The Royal Palace in Phnom Penh to ordinary folk like myself is quite similar in style to the Royal Palaces of Bangkok and Vientiane and so depending on where else you've been you may have had enough of South East Asian palaces. If this is the case it wouldn't be the end of the world if you didn't go however, if you haven't, it is definitely worth going as these building are impressive and provide insight into the countries history and culture.
National Museum of Cambodia
There are some interesting things inside this museum but the building itself is really great. It is a beautiful red building tucked out of the way and surrounded by lovely gardens. A great place to spend a sunny afternoon for tranquillity in the city.