The sinking hillfort with a secret turret

Eržvilko piliakalnis, the sinking hillfort, is located in Jurbarko rajon, near the confluence of Šaltuonos and Eržvilkų rivers. It is triangular, with a southern-western entrance, 27 meters long and 20 meters wide. A 4-meter-high turret can be seen from a height of 31 meters, a 16-meter-long and 30-meter-wide moat surrounds it, and the western part of the hillfort has a 2-meter-high and 12-meter-wide mound. The nature of the hillfort is undergoing changes, with part of its surface nested, the mound's surface cracked, and the hillfort sinking slightly.

Sources: Wikipedia, OpenStreetMap, Wikidata, Wikimedia Commons