Leonardo da Vinci created an ideal city concept designed to improve sanitation and movement after the plague in Milan.
During the late fifteenth century, Leonardo developed plans for a more orderly urban settlement with separate levels for different types of traffic. His proposals included waterways, drainage, access routes, and arrangements intended to reduce crowding and improve cleanliness.
The plans followed the devastating plague outbreak that struck Milan in 1484–1485. Leonardo believed that urban design could help limit disease by improving ventilation, waste removal, and the movement of people and goods.
The ideal city was never built as a complete settlement. It is therefore best understood as a planning concept, not a constructed city or a single architectural invention.