The Compass Tower was a tall structure located amidships, on the Boat Deck. It was located on a raised area, in a place where there was the least interference from the magnetic field put out by the iron in the ship's hull.
The compass platform itself and the compass are gone from the wreck. The raised roof for the platfrom was near is still visible on the bow section. The platform and compass have not been found.
On the Olympic, the tower was located amidships, on the Boat Deck. Later on, the compass tower was removed and a compass was added above the Bridge.
On the Britannic, the compass tower remained amidships on the Boat Deck. However, another compass was installed above the Bridge.