Medan, the conference location. It is the capital city of North Sumatera, where you can see Maimun Palace, becak (rickshaw) and many culinary stalls.
Lake Toba (in Parapat/Samosir Island), around 5 hours by car from Medan. Lake Toba (Indonesian: Danau Toba) is a large natural lake occupying the caldera of a supervolcano (wikipedia). Lake Toba is one of the awesome natural wonders of the world. This enormous crater lake has an island almost the size of Singapore in its centre. At over 1,145 square km, and a depth of 450 meters, Lake Toba is actually more like an ocean. This is the largest lake in Southeast Asia and one of the deepest lakes in the world.
Waterfall Drops into Indian Ocean in Mursala Island. Mursala Island is located in Central Tapanuli Regency, the east coast of North Sumatra. Mursala is the biggest island in Central Tapanuli district, North Sumatra and was used once as a place to make the Hollywood movie KingKong (2005) for it’s amazing scenery.
Meet elephants in Tangkahan, Langkat. It is 3-4 hours travel by public transport from Medan.