The ancient city of Koh Ker had a very brief spell as the capital and center of the Khmer Empire, between 928 and 944 CE. The capital was then moved back to Angkor Wat.
A new study has used ground-penetrating radar and manual excavation to uncover some of the hidden structures of the Koh Ker settlement, discovering a chute some seven kilometers long (4.3 miles), designed to ferry water from the Stung Rongea river to the city. But the chute has been calculated to be too small. This meant there were likely overflows and flooding, and the water would end up being wasted, without reaching where it was supposed to go.
In 944 CE after just 16 years in Koh Ker, King Jayavarman IV decided to move the capital back to its previous location in Angkor Wat. It was probably no coincidence that Angkor Wat’s water infrastructure actually worked.