Relics of the Mesolithic settlements, from 8000 to 4000 BC, are also found in the same places as those of the Paleolithic age but these are located closer to the forests. Historical remains from the Iron Age, from 500 BC to 1000 AD, are found on the hills. Hill forts are the most significant historical relics in Lithuania. Presently, these form one-third of the archaeological monuments of Lithuania.
The country is dotted with hill forts which exhibit the architectural style of the early people. Some of the well-known forts are Bubiai and Brazuole hill forts in Trakai region, Merkine and Liskiava forts in the region of Varena, Punia hill fort in the region of Alytus, Veliuona hill forts in Jurbarkas region and the castle hills of Vilnius Castles.
Pagan sites called Alkai, located close to the ancient settlements and the hill forts, also are archaeological sites in Lithuania. These places were the sites of sacred fire, sacred offerings and other rituals.

