Caer ‧ nar ‧ fon BrE AmE , Caernarvon /kəˈnɑːv ə n $ kɑːrˈnɑːr-/
a small town in northwest Wales, known for its castle where the British king or queen’s oldest son is given the official royal title Prince of Wales . Prince Charles’s ↑ investiture (=ceremony for receiving this title) took place there in 1969.