Tavern puzzles are mechanical puzzles consisting of two or more pieces of metal or wood, sometimes connected by a string or cord, which are loosely intertwined. The object of these puzzles is to figure out how to separate one piece from the other(s). The solution never involves bending metal bars or breaking any part of the puzzle, though it may seem impossible to do it otherwise. The Alcatraz puzzle is not exactly a tavern puzzle, but is closely related.