Poolside at Tri Lanka.

Lush greenery beckons at the eco-luxury hotel.

Perched on the edge of Koggala Lake just inland from Sri Lanka’s southern coast, Tri Lanka is the island’s latest forward-thinking eco-luxury hotel, conceptualized to mirror the ancient Fibonacci sequence (golden ratio) of nature. The 10 sleek suites have an enchanting tree house-luxe charm, with “living” walls and gardened roofs that spiral down a hill crowned by a cinnamon-stick-clad water tower, which contains three more guest rooms of its own. Waking up each morning to the soothing chorus of birds and lungsful of fresh air guarantees a tranquil start to the day. The cuisine here is equally innovative, built around an array of quality ingredients that impart fresh Sri Lankan flavors with a fine-dining touch: think lentil wade (a popular local street food) infused with lemongrass, or the irresistible sweetness of white-tea panna cotta with jaggery ice cream. Tip: If you’re not up for the three-hour drive from Colombo’s Bandaranaike International Airport, opt for a seaplane flight instead: local outfit Cinnamon Air can get you to Koggala in just 35 minutes. (94­ 777/708­ 177; trilanka.com; doubles from US$270).