The Piliakalnių Hillfort is located in the northwestern part of Marijampolė Municipality, near Šunskai, on the left bank of the Rytupis River (Šunskai Eldership). You can reach this site by driving on the Marijampolė–Šunskai road, turning towards Kazliškiai after Šunskai, and then turning left towards the west at Sarakai. After 920 meters, when the road bends to the left, turn right towards the north and, after 190 meters, you will arrive at a homestead where the hillfort is located.
The hillfort is situated on a small hill that juts into the Rytupis Valley. It measures 120 meters in length from east to west, with a maximum width of 90 meters. The slopes of the hillfort on the valley side are steep, approximately 4 meters high. The area is triangular in shape, extending in a northeast–southwest direction, 25 meters long and 27 meters wide at the northwest end, where there
is a rampart 30 meters long, 1.5–2 meters high, and up to 12 meters wide. Beyond the rampart, there is a ditch 8 meters wide and 0.5 meters deep. The hillfort is surrounded by linden trees, which add natural beauty to the area.
To the south of the hillfort, there is a settlement at the foot covering 0.3 hectares. Two causeways were discovered to the north of the hillfort across a swamp: one measuring 20x3 meters and the other 40x0.6 meters, located 150 meters south of the first. The hillfort dates back to the 1st millennium AD and was declared a national archaeological monument in 1972. In 1997, it was included in the Lithuanian Cultural Heritage Register, and by Government Resolution No. 612 on May 19, 1998, it was declared a cultural monument. On April 29, 2005, it was recognized as a state-protected monument. The total area of this cultural heritage site is 0.30 hectares.