Devils Battery or Devils Point Battery, Hartlen Point or Hartlen Point Tunnels, was a complex military installation at the mouth of Halifax Harbour in the community of Eastern Passage at , Canada. It was built between 1940 and 1945 to protect the Halifax area against the German navy. It was operational until the 1950s. The site had three 9.2 inch (234 mm) breech-loading Mark X guns, operated by the 53rd Heavy Battery of the 1st (Halifax) Coast Regiment. It is now a golf course; the original underground armaments remain buried. Devils Battery was named for Devils Island which is adjacent to the embankment of Hartlen's Point.