Lonely Planet review for Ponte Vecchio
The first documentation of a stone bridge here, at the narrowest crossing point along the entire length of the Arno, dates from 972. The Arno looks placid enough, but when it gets mean, it gets very mean. Floods in 1177 and 1333 destroyed the bridge, and in 1966 it came close to being destroyed again. Many of the jewellers with shops on the bridge were convinced the floodwaters would sweep away their livelihoods; however - fortunately - the bridge held.
They're still here. Indeed, the bridge has twinkled with the glittering wares of jewellers, their trade often passed down from generation to generation, ever since the 16th century, when Ferdinando I de' Medici ordered them here to replace the often malodorous presence of the town butchers, who used to toss unwanted leftovers into the river.
The bridge as it stands was built in 1345 and was the only one saved from destruction at the hands of the retreating Germans in 1944. What you see above the shops on the eastern side is the infamous Corridoio Vasariano built rather oddly around - rather than straight through - the medieval Torre dei Mannelli at the bridge's southern end.