Tonglu is the one of the higher peaks of the Singalila Ridge and a small settlement inside the Singalila National Park in the Darjeeling subdivision, Darjeeling district in the state of West Bengal in India near the India - Nepal border. It is a roadside halt along the trekking route from Manebhanjan to Sandakphu.It was also known as Tonglo in the 1800s.When Sir Joseph Dalton Hooker carried out many plant hunting expeditions in Darjeeling and Sikkim.GeographyTonglu is located at.