Aeclanum (also spelled Aeculanum, Italian: Eclano) was an ancient town of Samnium, southern Italy, c. 25 km east-southeast of Beneventum, on the Via Appia (near the modern Mirabella Eclano). It became the chief town of the Hirpini after Beneventum had become a Roman colony.
Sulla captured it in 89 BC by setting on fire the wooden breastwork by which it was defended, and new fortifications were erected. Hadrian, who repaired the Via Appia from Beneventum to this point, made it a colony; it has ruins of the city walls, of an aqueduct, baths and an amphitheatre; nearly 400 inscriptions have also been discovered.
Two different routes to Apulia diverged at this point, one (Via Aurelia Aeclanensis) leading through the modern Ariano to Herdoniae, the other (the Via Appia of the Empire) passing the Lacus Ampsanctus and going on to Aquilonia and Venusia; while the road from Aeclanum to Abellinum (mod. Avellino) may also follow an ancient line.
In late antiquity the city was an episcopal see. The most well known of the bishops of Aeclanum was Julian of Eclanum during the 5th century. With the Lombard invasion of Italy it was annexed to the Duchy of Benevento, until it was finally destroyed by the Byzantines of Constans II in 663, reducing to a small hamlet known as Quintodecimo (referring to its distance of 15 miles from Benevento). However, until today Aeclanum is a titular diocese of the Catholic Church
- Aeclanum (with photographs)