Tonglu is actually one of the peaks of Singalila range and located at an altitude of 10,130ft. Earlier in 1800s this place was part of Sikkim and known as Mount Tonglo. Tonglu is a small settlement and a mountain hamlet along the route to Sandakphu and located in Darjeeling district.
Tonglu is about 2kms from Meghma and it takes about 1 hour trek to reach the GTA lodge from Meghma. The Gravel road for vehicles (which is also the trek route for most part) comes here from Meghma and continues ahead to Tumling which is another 2kms away. Trekkers not willing to stay overnight at GTA lodge can also take a diversion (a trekking trail) before reaching the GTA lodge and go down to Tumling on a route which is a little shorter).