There are lots of amazing sites to see around Colombo, including the Lotus Tower, Pettah Markets, Port City (water sports, shopping, restaurants), Mount Lavinia beach, Galle Face Green, Independence Square, Gangaramaya Temple, Red Mosque and lots more!
Local transport is easily accessible from Colombo, so you can also take trips to other parts of Sri Lanka during your free time. At the weekend, we recommend hopping on a 2 hour train ride to the south of Sri Lanka to explore the stunning beach towns. (Ps. the views of the coastline on this train ride are beautiful!)