| Alte Burg | |
| Native Name: | Alte Burg im Quecken, Alte Burg "am Quecken" |
| Built: | 9th century |
| Type: | hill castle, spur castle |
| Condition: | remains of foundations |
| Materials: | rubble stone |
| Location: | Bad Münstereifel |
| Coordinates: | 50.5585°N 6.7695°W |
| Map Type: | North Rhine-Westphalia#Germany |
| Code: | DE-NW |
The Alte Burg (also Alte Burg im Quecken or Alte Burg "am Quecken") in Bad Münstereifel, Germany, is a circular rampart that is the remains of a fortification from the Carolingian period. The refuge castle acted as a place of retreat for the local population and as protection for the daughter monastery of Prüm Abbey. The defences dating to the 9th century have been designated as a protected monument. The castle site lies within the county of Euskirchen in the state of North Rhine-Westphalia.
The spur castle site lies northeast of the town centre on a hill spur, the second Quecken, above the Erft valley east of the B 51 federal highway at a height of 315to. It is long and wide, excluding the outworks.There were at least two periods of construction. In the northeast is a motte.
In the highest section of the site, the rubble stone foundation of a round tower has survived. In the 19th century a silver coin bearing the image of Louis the Pious is supposed to have been found here; it has not survived. In 1972 parts of the site were archaeologically investigated. During the excavations shards of pottery from the 9th century with decorations (Rollrädchenverzierung) were discovered.