- A Geological Mystery: The Nilavarai well is a natural underground water well formed by a collapsed limestone cavern. It is locally known as the “Bottomless Well” because it has never dried up, even during severe droughts.
- Dual Water Composition: The well’s water has a unique composition. The first 18.3 meters (60 feet) contains fresh water, which becomes progressively saline further down, indicating a connection to an underground saline water source.
- Dispelled “Bottomless” Myth: While long believed to be bottomless, the well’s depth has been measured at around 52 meters. Explorations have also suggested the presence of tunnels branching in different directions from the well.
- Archaeological Significance: The area around the well has significant historical and archaeological value. The discovery of a limestone Buddha statue and the remains of an ancient stupa and other buildings suggest a forgotten Buddhist heritage in the region.
- Connection to Keerimalai: There is a long-standing local belief that the well is connected to the Keerimalai Freshwater Pool, located about 10 kilometers away. The folklore states that a lime fruit thrown into the well will reappear in the Keerimalai sea.
