Rumah Bolon (Bolon house) near Toba lake, Sumatra, Indonesia
Danau Toba, Sumatra - Indonesia (Yasu's recommendation so it's on my list!)
Danau Toba, Medan, Sumatra Utara, Indonesia.
Tabo Cottages, Lake Toba, is a lake and supervolcano located in the middle of the northern part of the Indonesian island of Sumatra. Lake Toba is the largest volcanic lake in the world. - Alexander Ipfelkofer