Angkor Wat
Often called the mother of all temples clearly marks the main attraction when visiting the Temples of Angkor. Get there early in the morning, before sunset or climb up the nearby hill, slap a 300mm+ lens on your back (Angkor is 1,3 km away) and this is what you get. Stunning and worth the bumpy ride, either from the Thai boarder or the capital, on dirt roads getting there.
Sunrise (top), Hill (mid higher), Detail (mid lower), Sunset (bottom)

