The Fishing rod is an obtainable item in some Zelda Games. In other Zelda Games it is a loaned item at a Fishing Pond that has to be given back before you leave.
Ocarina of TimeEdit
The Fishing Rod is a loaned item at the Fishing Pond in both timelines Link can catch bigger and bigger fishes so he can obtain a Gold Scale and Heart Piece.
The fishing Rod is an obtained item at the beginning of the game. Link can use it to catch Fish to enter in his Fish Journal. Also Link can be loaned a Lure Fishing Rod at Hena's Fishing Hole to Fish for Larger Fishes.
Link can obtain the Fishing Rod. He uses it as part of a sidequest to get a Heart Container.