On March 18, 1990, about 40 pieces of art by Vermeer, Rembrandt, Degas, Manet, etc. were stolen from the museum. The thieves have never been caught.  It was the largest art theft in US history. 

Isabella Stewart Gardner Museum

The Isabella Stewart Gardner Museum or Fenway Court, as the museum was known during Isabella Stewart Gardner's lifetime, is a museum in the Fenway-Kenmore neighborhood of Boston, Massachusetts, located within walking distance of the Museum of Fine Arts and near the Back Bay Fens. The museum houses an art collection of world importance, including significant examples of European, Asian, and American art, from paintings and sculpture to tapestries and decorative arts. It is the only private art collection in which the building, collection, and installations are the creation of one individual.

• http://en.wikipedia.org/wiki/Isabella Stewart Gardner Museum