Vastseliina Castle was a castle of the Livonian Order, Bishopric of Dorpat. It was constructed by 1342 by the Landmeister Burkhard von Dreileben as part of the border fortifications of Old Livonia against Novgorod, Pskov and later Moscow. 

Nowadays the ruins of the castle are located near Vastseliina (in Vana-Vastseliina village), Võru Parish, Võru County, Estonia.

Source: Wikipedia