The Ackeburg, also called the Ackenburg,[1] in the Harz Mountains of central Germany, is the site of a high medieval hill castle, 333.2 m above sea level (NN), in the borough of Falkenstein/Harz in Harz district in the state of Saxony-Anhalt.

[2] The ruins of the Ackeburg are located in the eastern part of that region of the Harz known as Mansfeld Land between Mägdesprung (north of Harzgerode) and Meisdorf (southwest of Falkenstein/Harz) on a rocky ridge (333.2 m above sea level (NN)[3]) high above the valley of the River Selke on its northern flank.

[2] Today only parts of the neck ditch and transverse rampart are visible.

[1] The Ackeburg may be reached on woodland paths from Meisdorf, including the Meisdorfer Trift that runs past the Eckartsberg (330.5 m above NN) and Wilhelmsberg (329.8 m above NN) hills and finally up the Lumpenstieg trail.

Like the castle, the Selkesicht viewing point may also be reached via the Lumpenstieg trail, which drops steeply into the Selke valley from a point a little further east down to the inn of Zum Falken, where it meets the Selke Valley Trail and the E11 European long distance path.