Back in the old days, one of the easiest way to raise money for a bridge’s maintenance was to rent space over the bridge to merchants and shopkeepers. Today, only four such bridges exist in the world. Update: Apparently, there are a few more. Pont des Marchands in Narbonne, France, is one example.

The Ponte Vecchio or the “Old Bridge” over the Arno River, in Florence, Italy, is one of the most iconic medieval bridges. The bridge has been home to shops across its span since the 13th century. Merchants would sell their goods on tables after receiving approval to do so from the proper authorities. When a merchant couldn’t pay his debts, the table on which he sold his wares (the "banco") was physically broken ("rotto") by soldiers, effectively shutting down their business. This practice was called "bancorotto" and is believed that the economic concept of bankruptcy originated here.

Photo credit: Justin Mier/Flickr