A sex museum is a museum that displays erotic art, historical sexual aids, and documents on the history of erotica. They were popular in Europe at the end of the 1960s and during the 1970s, the era of the sexual revolution. Since the 1990s, these museums are often called erotic museums or erotic art museums instead of sex museums. There is a small sex museum in the heart of the Amsterdam red light district, de Wallen, and a second larger and more upscale one (Venus Temple) nearby, on the Damrak. Venus Temple is the oldest still operating sex museum; it opened in 1985.