‘Bamboo Port’ SP, Sri Lanka
From Sin: uṇa, ‘bamboo’ [Bambusa vulgaris]; and paṭṭana/paṭuna, ‘sea port’, ‘trading town’.
The sound change ‘paṭṭana/paṭuna‘ → ‘waṭuna‘ is fairly regular.
There is another derivation based on the Ramayana epic. Hanuman, the monkey-god, was sent back to the Himalayas to fetch the four medicinal herbs to heal Lakshman who was wounded trying to free Princess Sita her kidnapper, the demon king Ravana. Hanuman could not find these herbs, so he brought a whole mountain instead and carried it to the battlefield. He dropped a piece of it and Unawatuna is named after the place where it ‘fell down’ [Sin: wæṭuṇā, ‘fell’]. A nice story but sadly unconvincing.
Unwatuna is a coastal resort with plenty of beaches, surfing, snorkelling, coral reefs and, of course, the local celebrity, the purple-faced langur.