What is the smallest rain forest in the world?

As of 2014, the smallest rain forest in the world is the Bukit Nanas Forest Reserve, which is contained within the city of Kuala Lumpur in Malaysia. The approximately 25-acre patch is the only remaining stand of the jungle that once covered the area now taken up by the city.

The Bukit Nanas Forest Reserve is the oldest permanent forest reserve in the Malaysia. It was dedicated in 1906 to preserve an area of virgin rain forest within the developing city. Despite its small size, the preserve is home to native monkeys, monitor lizards, pythons and squirrels, as well as tropical tree species like the pulai, meranti and Keruing.