This is the Dom Luís Bridge in Porto, Portugal. It was designed by Gustave Eiffel, the same Eiffel of Eiffel Tower fame. At 564 feet clear span, it was the longest metal arch bridge ever built at the time of it’s construction. Turns out in addition to the famous tower, he designed other structures and dabbled in architecture as well, designing several major train stations as well as many other bridges throughout Europe. Ambitious little spud, wasn’t he…