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The next destination shall be Bukit Lawang. It is the only original habitat of Orangutan left in Sumatra. Bukit Lawang is located in the Gunung Leuser National Park on the border between North Sumatra and Aceh. You must go back to Medan first which take around 4 hours driving from Parapat, then continue 3 hours driving through palm and rubber plantation. Since the road is quite poor, especially on the plantation area, you should arrive Bukit Lawang before night. It means you shall start your journey at 10 am from Parapat or 9 am from Tuk-tuk.