If you take a walk along Kaunas Reservoir or next to the wharf or Pažaislis Abbey, you can find Pakalniškiai Hillfort. Travellers say that it is worth climbing this 27 m. tall hill because the view from the top opens onto the Kaunas Reservoir, Pažaislis, Kaunas Hydropower Dam and the old industrial area of Petrašiūnai.
If the legend is true, the Hillfort was built by ancient Lithuanians. It accommodated a wooden castle of Vaišvydas, a ruler of Nemunas Valley, who protected the land from enemies. Vaišvydas subordinates lived in Nemunas Valley. But the enemies completely destroyed the castle with the help of betrayers, and it wasnever rebuilt.
More information:
https://www.aplinkmarias.lt/en/sightseeing-places/pakalniskiai-hillfort-with-foremost-fortification/