Los Arcos Aqueduct

Though it was built between 1537 and 1558, this aqueduct looks very Roman from a distance, with its two layers of semi-circular arches. It's one of the most significant works of engineering from the Spanish Renaissance.

As you get closer, you can see that the lower story is not just a structural feature that gives the aqueduct increased height—it also serves as a pedestrian overpass. People could walk along the lower level while water streamed along the channel on top.

The structure is still in use as a footbridge between the medieval and modern parts of Teruel, Spain. But people are now the only things to flow across it, as the water, which originated from a spring about four miles away, no longer flows. 

The aqueduct's design was the work of a Frenchman Quinto Pierres Bedel, and as such, it is sometimes called the French Aqueduct.