Thanamalwila is located north of the Hambantota town and borders along the main river system which often rages when there is ample rainfall.. The unique ecosystem offers varying levels of wildlife which cannot be found in other parts of Hambantota. For example: Thanamalwila River. Thanamalwila River. Thanamalwila is located north of the Hambantota town and borders along the main river system.. This area is mostly untouched by tourists and is a great place to just hang out near the river.. The only people you would find are a few vilagers that come to bathe.