Conversation so far:
Where does Celtic art come from?
The Early Medieval art of Britain and Ireland is what Celtic art evokes for much of the general public. Celtic art also includes the Pictish art of Scotland.
What are the influences of Celtic art?
Archaeologists identified various cultural traits of these peoples, including styles of art, and traced the culture to the earlier Hallstatt culture and La Tène culture.
What was the Hallstatt culture that archaeologists traced the culture of Celtic art to?
The earliest archaeological culture that is conventionally termed Celtic, the Hallstatt culture
What are popular pieces of Celtic Art?
Hanging bowl, Carpet page, High cross, Pictish stone, etc.
Are there any other interesting aspects about this Celtic art article?
Continental Celtic culture in the Iron Age featured many large fortified settlements, some very large, for which the Roman word oppidum is now used.

Question: What does the word mean?
Self-contained rewrite: What does the Roman word oppidum mean?