Angkor Wat is a temple complex and was the capital city of the Angkor (aka Khmer) civilization in Cambodia, built by Suryavarman II between 1130 and 1150 AD. The word "wat" refers to a temple or monastery.
The site is comprised of a large temple pyramid surrounded by a 700ft wide moat and has stunning sculpted murals (bas-relief) on its interior walls. It holds the Guinness Book of World record for "largest religious structure in the world". Besides that prestigious award ^^, Angkor Wat was also named as a UNESCO World Heritage Site in 1992.