The Fort Knox State Historic Site and new Penobscot Narrows Observatory are outstanding examples of 19th and 21st Century engineering marvels. Fort Knox is one of the best-preserved Civil War-era forts. This massive granite fortification overlooks the Penobscot River and is rich with interpretive displays. The new Penobscot Narrows Observatory allows visitors to ride an elevator 420 feet above the Penobscot River, for 100-mile panoramic views of the Penobscot River Valley. The Observatory tops the award-winning, cable-stayed Penobscot Narrows Bridge, constructed to replace the Waldo-Hancock Bridge. Fort Knox and the Observatory are open from May 1 to October 31. Both venues are available for weddings, corporate events, parties, reunions.