Here’s how the Ponte Vecchio looks today:

And here is how it looked 48 years ago today:

Here’s a detail showing how the flood waters were not the only aspect of the disaster, but the debris including downed trees also hit the famous bridge.

Santa Maria Novella piazza under high waters:

Flood waters moved and destroyed thousands of cars.

You can read more about the flood here:

http://www.theguardian.com/artanddesign/2013/dec/26/vasari-last-supper-reassembled

You can see footage here: