The Middle Ages were a restless time in Ilomantsi. The Karelian people faced the approach of enemies from both east and west. In order to defend themselves from the threats, the local people started constructing defensive walls on top of Havukkakallio. The hillfort was built throughout three distinct time periods. During the first period, between the early 1300s and early 1400s, defensive wooden structures were constructed. This original structure was rebuilt and improved in the 1400s. In the 1500s, the old walls were elevated by covering the pre-existing wooden structures with soil. In the early 1800s, Havukkakallio was used as an execution site. One person lost their life here just before the death penalty was abolished in what was then the Grand Duchy of Finland. Stories about this execution feature prominently in the oral histories of Ilomantsi. People told their children stories of the ghost of Havukkakallio and told them not to visit the area, as it was considered a ‘bad place’. Other stories about the area mention a spring that produces the ‘water of life’ and where a great treasure is hidden. A cross symbol, cut in the bedrock, can be found on the hilltop. The origins and meaning of the cross are not known. Local stories speculate that this cross marked the location of the execution site. Another possible explanation is that cartographers from the 1800s or early 1900s used this spot as a topographic checkpoint and marked it as such.