Angkor Archaeological Park is a UNESCO designated World Heritage site. It's home to a myriad number of temples, some of which are in ruins, others claimed by the jungles and others are the largest of their kind on earth. Generally its THE star draw to Cambodia. The whole thing gets more popular by the year, but the attention it's given to make it worthwhile increases too. A day pass is $37, but take the 3 days at a minimum if you can, thats $62. You'll easily be able to arrange a moto driver for those days and you'll pay them separately, but those guys will look after you so well. Angkor Wat is the highlight of course, get there for Sunrise as its simply awe inspiring, Ta Phrom was in Tomb Raider and is covered in jungle, The Bayon just watches you from every angle...