Brasat Muang Tam, Buriram, Thailand

This one is down in the flats, near the "mountain" temple Panom Rung. The water feature appearing in this video is unique in my experience. Those "four corners" pools. The whole temple had water channels everywhere, around the buildings, across the building entrances, water was a big part of their worship.

From what I hear, the entire Angor Wat complex in Cambodia was an elaborate water puzzle. It was designed so that during the rainy season everything would fill up, water surrounding everything, water for luck, water showing the power of the king. This here temple is Angor Wat Junior.