Mount Lavinia Beach is one of Colombo's laidback areas. There are many seafood restaurants on the golden beach, where you can enjoy some local seafood and if you plan it right, enjoy a wonderful sunset.
Visit a Temple
The Gangarama Vihara is one of the most renowned temples in the country. The temple is decorated with brass work, carvings and Buddhist art. If you'd like to learn more about the history of the temple there is a museum located on the inside.
Other things you can do: