A racing boat moves along the Tonle Sap for pre-race practice runs. Many event spectators have come from distant regions of Cambodia, and camp along the river banks for the duration of the festival. Cambodia’s annual 3-day water festival celebrates the reversal of the flow of the Tonle Sap River - an event of large cultural significance because of the river’s role in national fishing and agriculture. The event was cancelled for three previous years in a row after the stampede incident in 2010, when nearly 350 people were killed and roughly 750 more were injured.