The Sylter Heimatmuseum in Keitum is the best place to put Sylt's polished resort surface into context. Exhibits cover island houses, seafaring families, whaling, traditional dress, and the North Frisian culture that shaped Sylt before beach tourism took over.
The museum works especially well with a walk through Keitum, where old captains' houses and thatched roofs still give the village a different rhythm from Westerland. It is a modest stop, but a worthwhile one if you want the island to feel like more than dunes and expensive restaurants.