An
oppidum (plural
oppida) is a large fortified
Iron Age settlement. Oppida are associated with the
Celtic late
La Tène culture, emerging during the 2nd and 1st centuries BC, spread across Europe, stretching from
Britain and
Iberia in the west to the edge of the
Hungarian plain in the east. They continued in use until the Romans began conquering Europe. North of the
River Danube, where the population remained independent from Rome, oppida continued to be used into the 1st century AD.