Nilavarai is a natural underground well at Puttur, roughly 14 kilometres from Jaffna town. A collapse in the limestone surface long ago exposed a water-filled cavern whose level never drops — even in drought — and which still feeds irrigation for the surrounding fields.
Long called bottomless, it has in fact been measured: a nineteenth-century study found a base around 145–150 feet, while a later Sri Lanka Navy dive expedition using a robot recorded about 52.5 metres and branching underwater tunnels. The water is fresh in its upper layers and turns brackish roughly forty to fifty feet down. Legend holds that Rama struck the ground with an arrow here to quench his thirst, and tradition links the well underground to the Keerimalai spring — a connection never proven, and better for it.
Good to know
- A quick, fascinating stop — combine with Kandarodai and the north coast
- Locals swim here; the jump is for the confident
- The fresh-over-salt layering is real science behind the legend
- Little shade at midday — mornings are best