Parapat is a small town on the edge of Lake Toba.
From Medan there is a local bus (no air-con) about every hour for 22,000 rupiah (Oct 08) if you pay on the bus. The journey takes 4-6 hours, depending on the traffic condition.
10,000 IDR/person to Tuktuk, and to Tomok is 5,000 IDR/person in Tiga Raja jetty; they had other jetty in Ajibata with the same price 5,000 IDR/person to Tomok; just take 30 minutes from Tigaraja Jetty/Ajibata jetty to Tomok or Tuktuk. First boat from Tigaraja Jetty to Tuktuk start from 08.30 AM - 07.00 PM; every hour trip; and to Tomok they had last boat at 07.00 PM.
Welcome to the “River Rafting” Best-3 in The World; Asahan River is a river in North Sumatra which flows from Lake Toba. This river passes Porsea, district Asahan, and ends at Nibung Gulf, the Strait of Malacca. Rivers that have a length of 150 km, also pass through the valleys of the Barisan Mountains. Asahan River especially around the Tangga village, District Bandar Pulau, has a speed of 120 m / sec with grade IV-V + with an average depth 5meter very challenging, especially whitewater rafting enthusiasts. River which is the best rivers for whitewater rafting to 3 has four lines with different difficulties.