Gradina on Liska Cava is an early Byzantine fortress on a hill in the village of Lis, which is located approx. 5 km from Guca. Gradina on Liska Cava consists of the upper and lower town. The total area of the city is approx. four hectares. The preserved height of the walls is up to two meters and there are remains of two towers. It is believed that the fortress had both military and civilian purpose. At the site were found parts of ceramics from the fifth century were found on the site, as well as materials dating from the sixth and early seventh century. Golden coin minted in Constantinople between 524 and 565 years were foe fortress belongs to the period of the Emperor Justinian.