Sinharaja survived because people fought for it. Mechanised logging in the 1970s was halted after a public campaign, and the forest went on to become an international biosphere reserve and, in 1988, a UNESCO World Heritage Site. More than 60 percent of its trees are endemic, and an estimated 240,000 plants grow on a single hectare. This full day enters from Kudawa on the northern edge with a licensed DWC naturalist who knows where the purple-faced langurs feed and where green pit vipers sit motionless at eye level. The route follows the main trail into the forest, pauses beside a clear stream for lunch, and climbs to a viewpoint where the canopy rolls out unbroken across the Kalu Ganga basin.