Eternal fire in the context of "Coal seam fire"

The Bylliones (Ancient Greek: Βυλλίονες) were an Illyrian tribe that lived near the Adriatic coast of southern Illyria (modern Albania), on the lower valley of the Vjosa river, in the hinterland of Apollonia. The Bylliones were firstly attested in epigraphic material from the oracle of Dodona dating back to the 4th century BC, and their koinon was firstly attested in a 3rd-century BC inscription from the same oracle. Their territory was trapezoidal on the right side of the rivers Luftinje and Vjosa, extending in the west to the Mallakastra mountains. The chief city of their koinon was Byllis. Another important centre of their koinon was Klos, an earlier Illyrian settlement later called Nikaia, as an inscription attests. The Bylliones also inhabited in the area of an ancient sanctuary of the eternal fire called Nymphaion.

Through contact with their Greek neighbours, in Hellenistic times the Bylliones acquired a certain degree of Hellenization and bilingualism, especially in the urban centres of their koinon. In Hellenistic times their koinon minted coins as attested by inscriptions reporting their ethnicon in Greek letters. The koinon of the Bylliones survived until Roman Imperial times. In the Roman era, the Bylliones reappear in the late 1st century CE when they are mentioned by Pliny the Elder in the Natural History (c. 79 CE) as one of the "barbarian" tribes which lived in the area of Nymphaeum. The koinon of the Bylliones and the koinon of the Amantes were the most notable Illyrian koina.

Nymphaion (Ancient Greek: Νυμφαῖον, Nymphaîon) was the name given to the ancient sanctuary of the "eternal fire" located in southern Illyria, notably near Apollonia, in modern-day Albania. The location also featured bitumen mines, which, still functioning today, have held a crucial role throughout the history of the region.

Placed inland on the Vjosë/Aoos river, the area was occupied by Illyrians since before archaic colonial times, and the site was likely already a place of worship because of its peculiar physical properties. Attested local tribes of the area were the Bylliones and the Amantes. In the 7th–6th century BCE Apollonia was founded on the Illyrian coast near this site by a joint colony of Corinth and Kerkyra. According to ancient literary tradition the fire of the sanctuary never went out before an ancient war fought between Apollonia and the Illyrians. Around mid-5th century BCE, after conquering nearby Thronion, Apollonia consolidated its control over the site of the fire sanctuary and the area of the bitumen mines. Until the Apollonian conquest, the control of the bitumen mines may have produced in part the wealth of Thronion.

The Amantes (alternatively attested in primary sources, as Amantieis or Amantini; Ancient Greek: Ἄμαντες or Αμαντιεῖς; Latin: Amantinii) were an ancient tribe located in the inland area of the Bay of Vlora north of the Ceraunian Mountains and south of Apollonia, in southern Illyria near the boundary with Epirus, nowadays modern Albania. A site of their location has been identified with the archaeological settlement of Amantia, placed above the river Vjosë/Aoos. Amantia is considered to have been their main settlement. The Amantes also inhabited in the area of an ancient sanctuary of the eternal fire called Nymphaion.

The Amantes firstly appear in ancient literature in the 4th century BCE in the Periplus of Pseudo-Skylax as an Illyrian tribe bordering the Epirote Chaonians. In Hellenistic sources they are mentioned among the Epirotes. In Roman-times literature they appear as barbarians. In modern historiography a number of scholars regard the Amantes as Illyrians, and others consider them as Epirotes.