The title Crown Prince is most often awarded to the eldest child of a monarch, such a king and is an indication of the person's rank as the heir tae the throne. It is a similar title to Hereditary Prince. Wewi the title are a Crown Princess. Several German principalities and duchies used the title Hereditary Prince to denote the heir to the throne.

Crown Prince Frederik of Denmark.
Crown Princess Victoria of Sweden.
Crown Prince Haakon of Norway.

List of some Crown Princes an Crown Princesses edit

Courtesy title by pretenders edit

In addition; the following heirs apparent to deposed monarchies use the title of Crown Prince as a title used by international courtesy: