A long-distance telephone call from Chet Morton's uncle summons Frank and Joe Hardy and their staunch pal Chet to a summer art school, located near old Fort Senandaga which is reputed to be inhabited by a ghost. The young detectives' assignment: recover two famous oil paintings stolen from the valuable Prisoner-Painter collection owned by Jefferson Davenport.
Mr. Davenport, millionaire sponsor of Millwood Art School, reveals that one of the famous Fort Senandaga pictures painted by his ancestor, General Jason Davenport, contains a clue to the hiding place of a priceless chain of gold.
Vicious threats and deadly traps beset Frank, Joe, and Chet as they search for clues to the stolen paintings and the gold treasure - a search that is complicated by a stormy feud between a proud Englishman and an equally proud Frenchman over the military history of the fort.
- George Ashbach
- Adrian Copler
- Alex (The chaffeuer)
- Jefferson Davenport
- Lloyd Everett
- Rene Follette
- Chauncey Gilman
- Jim Kenyon
- Ronnie Rush
- Myles Warren
Businesses and organizations
In the UK The Haunted Fort was published by both Sampson Low and Collins in 1966 and 1971, respectively. In both series The Haunted Fort is not #44, but in the Sampson Low series it is #36 and in the Collins series it is #3. 
- ↑ Who Wrote the Hardy Boys? at Keeline.com
- ↑ The Haunted Fort Major Edition Types at The Hardy Boys Unofficial Home Page
- ↑ http://hardyboys.co.uk/gallery/03.php
to be added.