UNESCO as a World Heritage Site and a Biosphere Reserve Beautiful forest with plenty of birds, including rarely seen owls. You could spend at least a couple of days there exploring different areas
Over 130 birds, species are found here including many of the 33 species endemic to the Sri Lanka. There also rich reptile population Mammals including the purple faced langur monkey and the giant squirrel. It is preferable to explore Sinharaja on foot, which makes for the truly authentic jungle experience.

I have seen here so far – green-billed coucal, Sri Lanka wood pigeon, Sri Lanka white-headed starling, ashy-headed babbler, magpie, Sri Lanka broad-billed roller, and jungle fowl,
Sinharaja is not along the way to any of the most visited attractions in the Island, hence you’ll have to allocate extra days to your itinerary to visit the place. There are 3 entrances to the forest reserve and the most used one is the Kudawa entrance The nearest big town is Ratnapura 35 miles away
I have stayed close by at Deniyaya and entered at Deniyaya Mederipitiya to the East
You can also enter at Kudawa to the North