The oldest elliptic arch bridge in the world spans the Arno river. It was constructed in the 16th century by Bartolomeo Ammannati, an Italian architect and sculptor who also worked on the Fountain of Neptune and carved the Neptune's face. The bridge was destroyed during the WWII and renovated in 1958 using the original stones.
Wikipedia https://en.wikipedia.org/wiki/Ponte_Santa_Trinita
Address 72-red Lungarno degli Acciaioli, Firenze 50123, Italy
Coordinates 43°46'8.652" N 11°15'1.386" E