The most attractive accommodation on Pulau Samosir is this sprawling German-run lakeside place that has the feel and professionalism of a laid-back resort. Rooms are inside blocks of beautiful Batak-style buildings, with huge bathrooms and hammocks, and there's a superb lakefront pool. Owner Annette is a treasure trove of information on Batak culture.
The homemade bread and cakes at the attached German bakery are worth a stop. They also roast their own coffee beans, which are grown on the island. Their tours are another highlight.