The Princess who was Hidden Underground

The Princess Who Was Hidden Underground is a famous German fairy Tale by Andrew Lang. This story is about a king who has three sons. Once king divided his property; the older two squandered theirs and soon had nothing, but the youngest son was cunning and clever and soon became rich. He had an underground castle built, but killed the architect and had his daughter imprisoned. The youngest son said that whoever could find her would marry her, but whoever tried and failed would die. Who is able to find a daughter? Read this attractive story in order to know the end!