- Gift Shop: The three arches in this room were laneways for Sir Henry's proposed bowling alleys.A shooting range was to have been installed on the other side of the wall but was never completed.
- Sir Henry's Cafe: Originally designed to be Sir Henry's private exercise room, it was to be filled with the latest of the turn-of-the-century equipment.
- Swimming Pool: The pool beneath the Conservatory was also never properly finished. The original plans called for the pool to be surrounded by cloisters, marble arches and gold swans around the edge. In fact, the pool and the entire basement of Casa Loma were used mainly for storage.
- Wine Cellar: Ammonia and brine-filled pipes chilled the collection of nearly 1800 bottles of wine and champagne, Sir Henry's drink of preference. It is interesting to note that the cellar is directly connected to Sir Henry's study by a secret passage.
- Tunnel to Stables: The stables are connected to the castle by an 800-ft. tunnel which runs 18' below the ground.