Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Medan (88% of total searches to North Sumatra). The next most popular destinations are Parapat (5%) and Lubuk Pakam (4%). Searches for hotels in Tongging (3%) are also popular.
KAYAK users have found double rooms in North Sumatra for as cheap as S$ 10 (Siborong-Borong) in the last 3 days. The average price is S$ 10.