After you get instructions from the Head Warrior of Shecola, you pass through the fourth cave and reach the fifth overworld area.

Visit the Poet

Stand one square west of the cave exit, then go straight south until you hit the mountains. From there, go west and you will enter a hidden cave in the mountains. Go southwest to exit the cave on the other side, then enter the house. Go west to reach the inside of the house, and talk to Po, the famous poet of the southern island. Po recites a poem:

Rain drops from heavens
Fountains spring from earth
Lifting my spirits high

Leave Po's house and go east until you're outside again. Then go southeast and enter the cave near Po's house.