There are 5 Heart Containers to collect outside of dungeons in The Legend of Zelda. In recent games, you would have to collect 4 or 5 Heart Pieces to create a Heart Container. Below, you can find out which sector of the Overworld to explore and what you have to do to get each Heart Container.

From where you start, go east four screens, and use a bomb on a nearby wall to reveal a cave.

From where you start, travel one screen east, three screens north, and one screen west. Burn down one of the bushes to reveal a stairway (the bush you have to burn is near the east part of the screen).

From where you start, head east four screens, north five screens, and one screen east (near Dungeon five). Use a bomb on the eastern side of the large rock to reveal a entrance.

From where you start, head east eight screens, and north five screens. (east two screens of the entrance of the Dungeon five). There you will find a place to use your raft; use it. After you cross the water, you'll see a house that resembles the look of a dungeon.

From where you start, head east eight screens, and north two screens. Use your ladder to get across the two platforms.