I stayed in the area for five days in November 2016.
The Kithugala area is the main place after Sinharaja that naturalists come to find rainforest birds, particularly species that are endemic to Sri Lanka. The Kelani River dominates the topography here. The name Kelani refers to this river, the area, and a beautiful rainforest reserve.
It takes about 3 hours by road to get to Kithugala from Colombo. There are several options for accommodation along the river that all have great views. I checked out Rafter's Retreat, the Plantation, and Kithugala Rest House. The latter is where I stayed while in the region.
The Kelani River dominates the scenery at Kithugala. At 145 kilometres in length, it is the 4th longest river in Sri Lanka. It starts in Horton Plains, and empties into the sea near Colombo. On the way it it used by rafters and for hydro-energy at Kithugala. It was also used as the location for filming some parts of the film "Bridge of the River Kwai".
There are several places to cross the river. There is a rickety bridge near the Plantation Hotel. Near the Kithugala Guest House there is a small plastic boat that punts across the river, which costs about a dollar for a tourist.
There are many different walks and variations.
Once you get over the Kelani River, the village and Kelani Reserve is great for walks and wildlife watching.
Once getting across on the ferry, there are several paths. Follow the path on the left through a tea plantation (the other two tracks go to houses). Once you get to a T-junction, the track to the right goes for several hundred metres through a quiet village to the National Park entrance.
There is another circuit walk through the village. Once you cross the river from the Rest House, if you go left at the T-junction, you can walk through the quiet village and you will eventually get to a rickety bridge that crosses the river. This takes you back to the town near the Plantation Hotel, and from here, if you follow the main road to the left, you get back to the Kithugala Rest House after a few kilometres.
The village across the river is quiet and good for bird and butterfly watching. There are no large roads or cars. Unusually for Sri Lanka, there are no vehicles speeding along beeping their horns constantly. Apart from the kids, the locals may not acknowledge you too much. They are probably sick of random tourists wandering through.
The Kelani Reserve is a great little area of rainforest. One of the best features about this place is that, unlike the busy and over regulated Sinharaja, you are allowed to explore this beautiful reserve by yourself.
There is often no one at the entrance in the morning, but you can always pay the $5 fee on the way back. Unlike most national parks, this one is very quiet and does not require a local ranger to baby-sit you. There is a large map at the entrance showing the walk; take a photo, it is quite accurate showing the tracks, the bends and where they cross creeks and rivers. Some of the creek crossings are stunning places. For a quiet rainforest, the tracks are well maintained. The only track I had problems with was the one that went up to the ridge to the temple.
There are many insects to be observed in the village, in the rainforest, and along the creeks.
Orange billed Babblers are endemic to Sri Lanka. They are often seen in naughty gangs in the village on the edge of the rainforest.
Brown-breasted Flycatchers have HUGE eyes compared to the size of their head. They often perch still on exposed branches in gaps in the forest.
The Asian Paradise Flycatcher, a beautiful and reasonably common bird through the forests of tropical Asia, is normally white as an adult male. The Sri Lankan subspecies retains brown upperparts throughout it's life.
Of course, Palm Squirrels are common in villages and gardens.
There is another rarer squirrel of a similar size that occasionally turns up in the village near the rainforest's edge. It is the 'Layard's Striped Squirrel' Funambulus layardi, sometimes known as the 'Flame-striped Squirrel'.