The Mitsui Memorial Museum opened in October 2005 in Nihonbashi, a site closely related to the Mitsui Group. The collections from the Mitsui Bunko Museum in Nakano ward, with many treasures of Japanese and Asian art, will move to the new museum. Members of the Mitsui families have assembled the art works in the collection over the past three centuries and their preservation as a collection make these art works a preeminent element of Japanese cultural heritage.