Much of the plan of the walled city we see today was established under Cambodia’s most renowned leader, King Jayavarman VII following his decisive turning of the defeat by the Chams (1177) into victory shortly thereafter. Angkor Thom was designed as the capital of an Empire that would dominate mainland Southeast Asia from at least as early as the end of the 12th century until the ascendancy of the Siamese to the west (in what is now Thailand) in the 15th century. The city was accessed by five impressive gates and causeways across the moat; four at the cardinal points plus the Victory Gate to the northeast. This extra gate spanned a pre-existing roadway between the Royal Palace and the cruciform terrace overlooking the East Baray.
The Chinese emissary Zhou Daguan, who visited Angkor at the end of the 13th century, describes the houses of the elite as being large and spacious, with carved walls and painted images of the Buddha. Buildings of the royal enclosure had tiles made of lead or yellow clay however fewer wealthy owners roofed their homes with thatch. All housing was constructed in wood and has all succumbed to the tropical conditions and especially the recycling efforts of termites.
The South Gate is the best preserved and also the busiest by far due to the tourist traffic between Angkor Wat and Bayon. It is well worth taking the time to climb up onto the wall and walk a little away from the gate to appreciate the view of the causeway. If you have more time, consider hiring a bicycle and riding around a section of the walls.
As you approach the 23m (75ft) high gate, you cross causeway flanked on either side by 54 gods (devas) and 54 demons (asuras) pulling on a giant snake in a representation of the scene from the Hindu myth of the Churning of the Ocean of Milk.
In this legend the gods and demons cooperate to create the nectar of life (amrita) that would render them immortal.
Using Mount Mandara as a pivot and the serpent (naga) Vasuki as the cord they churned until the mountain was on the verge of crashing into the sea. To help them, Vishnu, incarnated as the tortoise Kurma, bore the mountain on his back and recovered the amrita for the gods who, once rejuvenated, finally defeated the demons.