Malays, Batak and Nias.
Harditaher — CC BY-SA 4.0 · Naval Scene — CC BY-SA 4.0 · Ivens88 — CC BY-SA 4.0 · Naval Scene — CC BY-SA 4.0
The largest museum in North Sumatra, opened in 1982 on more than ten thousand square metres, showing the province's history and the cultures of its diverse peoples: the Malays and the Batak in their branches, the Nias, and the Javanese, Chinese and Indians who settled here over the centuries. Its halls hold traditional tools and weapons, costumes and textiles, models of traditional houses, and artefacts from prehistory to the colonial era, with a section on the coming of Islam to Sumatra and its sultanates. It is a good introduction to the province before a trip to Lake Toba and the Batak villages. Entry for non-Indonesians is about ten thousand rupiah; it opens Tuesday to Sunday from nine to four and closes on Mondays. The museum is quiet and little visited, needing an hour or two. Visit in the morning, then move on to Maimun Palace and the Grand Mosque.
Malays, Batak and Nias.
A section on Islam and its sultanates.
Before the lake and Batak villages.
Jalan H.M. Joni, south-east of central Medan
For museum lovers heading to Lake Toba, yes: it explains the Batak culture you will see there. If time is short, Maimun Palace and the Grand Mosque come first.