[1] This settlement may have replaced a previous Thracian tribal center called Sintia as the Roman historian Livy emphasized that Heraclea lay within the territories of the Sintoi.

Moreover, there is a conspicuous absence of Thracian names among inscriptions from Heraclea which also suggests that the Sintoi had been driven out of the Strymon Valley and that they did not intermix with the colonizers.

[4] A powerful earthquake around 425 AD destroyed the majority of the city's infrastructure, including the civic basilica, and also caused the nearby Strumeshnitsa River to flood the forum.

In essence, this is letter of Emperor Galerius and Caesar Maximinus II from 308 AD in which the rulers are turning to Herakleians in response to their request to reclaim the lost city rights.

Later on, after geosonar examination by Russian specialists, a large studio for producing ceramic masks for an unknown and as yet unrevealed ancient theatre was discovered.