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Where Michigan’s History Lives

Detroit Observatory

The Detroit Observatory was the first observatory built in the state of Michigan and is the second-oldest building on U-M’s campus. In 2005, the Detroit Observatory became a division of the Bentley Historical Library.

Having undergone a full restoration in 1998, the building stands essentially as it was in 1854. The Observatory is a cultural treasure waiting to be explored:

  • Come look through our telescope! The Observatory has public viewing nights hosted in conjunction with the Department of Astronomy. Viewing nights can be found by clicking here.
  • The Observatory has tours during the day as well, on select weekend dates each month from 1pm to 4pm.  To see all the daylight tour dates, see our events page.
  • The Observatory and its museum are available for guided tours, which can be made by special arrangement. The Observatory also occasionally permits small groups to use its meeting room. The room includes wireless access and a large projection screen. Please email Karen Wight at for more information.


1398 E. Ann Street (at the corner of Ann and Observatory Streets)
Ann Arbor, MI 48109-2051