Architecture:

The earliest surviving written work on the subject of architecture is De architectura, by the Roman architect Vitruvius in the early 1st century AD. According to Vitruvius, a good building should satisfy the three principles of firmitas, utilitas, venustas, commonly known by the original translation – firmness, commodity and delight. An equivalent in modern English would be:

Please answer a question about this article. If the question is unanswerable, say "unanswerable". When did Vitruvius create these plans?
1st century AD.