Sri Lanka is known for its natural beauty and beaches. Some famous beaches of SriLanka are Negombo, Mount Lavinia, Kalutara, Beruwela, Bentota, Hikkaduwa, Galle and Arugam Bay .
Dehiwala Zoo, Dutch Period Museum, Fort Clock Tower, Gangaramaya Temple, Independence Hall and Mt Lavinia Beach in Colombo are good to see.
I would suggest you to book a holiday package from a trusted travel portal, it will make your journey more enjoyable. If you book an all inclusive package from such travel portal, which would include travel, lodging, and even dinner reservations, all you'll be left doing is packing. They also advise you on local customs and other important things you need to know. Because of these facilities, I always take help from Yatra.Com and thats why I know the benefit of such packages than going independently.