Kalutara is a small coastal town about 42 kilometres south of Colombo, sitting at the mouth of the Kalu Ganga river where it meets the Indian Ocean. It has a pleasant palm-fringed beach, a modest centre of markets and busy roads, and two of the more distinctive sights on the southwest coast: the Gangatilaka Vihara, a hollow stupa whose interior chamber visitors can enter, and Richmond Castle, an eccentric colonial-era mansion built with exactly 99 doors and windows.
The town is well known for its mangosteens, which Sri Lankans consider the finest in the country. The fruit ripens from May to July and is sold at roadside stalls along the main highway through town.
Kalutara makes a convenient stop between Colombo and the beach resorts further south at Beruwala, Bentota, and Hikkaduwa, or a half-day excursion from the capital.