Petavonium was a Roman legionary fortress (castrum) established c. 25-19 BC in the Vidriales valley, Zamora province, Spain, during the Cantabrian Wars under Augustus. It housed a detachment of 5,000 legionaries from Legio X Gemina who guarded Asturian peoples and secured gold transport routes until 63 AD. After the legion departed, the Ala II Flavia Hispanorum -- approximately 500 Hispanic horsemen with Roman citizenship -- garrisoned the site until the mid-3rd century. Reconstructed watchtowers, gates, officers' quarters, baths, and a temple of Hercules are now open to visitors.
Petavonium

| Type | Fortress/citadel |
|---|---|
| Period | 1 - 500 AD |
| Country | Spain |
| Coordinates | 42.0890° N, 5.9980° W |
Spain