The Bertradaburg is a ruined hill castle on a rock spur, 348 m above sea level (NN), above the village of Mürlenbach in the county of Vulkaneifel in the German state of Rhineland-Palatinate.

In the castle, according to local tradition, Bertrada, the mother of Charlemagne is said to have lived which implies that his birth was around 747 AD.

The existence of the castle is first recorded in the 13th century when it is mentioned as a state fortress of the princely imperial abbey of Prüm (c.f.

In the late 20th century, the surviving castle walls and buildings were restored by the Tiepelmann family and the state-owned, 30-metre-high, ruined double tower gate was rebuilt with state finance.

In 2009, the nine owners were given a grant from the federal and state budgets to secure and maintain the 16th-century, five-metre-thick, southwest roundel.