Rialto Bridge, Venice

The Rialto Bridge, completed in 1591 by Antonio da Ponte, was the first permanent crossing of the Grand Canal and remained the only one for 300 years, costing over 250,000 ducats to build. Lined with shops and supported by 6,000 wooden piles driven into the lagoon floor, it reaches a single arch span of 28.8 meters. It is nearly 300 years older than #5 Tower Bridge, making it a Renaissance engineering marvel.