The Gauguin Museum Musée Gaugin, about 50km from Papeete on Tahiti Nui contains artifacts from Gauguin's time in Tahiti, including reproductions of many of his paintings. Open-air buildings and a gift shop are situated in a well-manicured lawn just next to the ocean, well away from the city and resorts. Botanical gardens are just next door.
The Museum of Tahiti and her Islands, about 15km from Papeete, contains really great displays of Polynesian history, culture and ethnology. Anyone who is interested in anthropology or the history of the Polynesian culture should see this museum.
For pearl lovers, there is also the Robert Wan Pearl Museum in Tahiti.