Karlsburg (German for "Charles's castle") may refer to:
Karlsburg, Mecklenburg-Vorpommern, municipality in Mecklenburg-Vorpommern, Germany Karlsburg Castle in Durlach in Baden-Württemberg, Germany a castle in Karlstadt am Main in Bavaria, Germany a German name of Alba Iulia in Romania
See also Carlsberg (disambiguation) Carlsburg (disambiguation) Karlsberg (disambiguation) Karlsborg