Container Locations

Below is the list of where and how to get the magic containers in Zelda 2:

Container 1 
Items Needed: None
Where: From North Castle, go east until you are clear of the moat, then south until you get to the mountains. Follow the southern wall west until you come to a secluded cave. 
How To Get It: Just enter the cave. 
Container 2 
Items Needed: None
Where: On Maze Island, follow the path round - but try and find the western most wall just north of the estuary.  
How To Get It: You'll find a pit - inside is the magic container. 
Container 3 
Items Needed: Hammer
Where: In Death Mountain, when you emerge from the cave containing the hammer. 
How To Get It: Break the western rock with your shining new hammer. 
Container 4 
Items Needed: None
Where: The House of Kasuto. 
How To Get It: Talk to the lady outside and she will invite you in. The magic container is at the back of the house.