The first thing we did when we got to Porto was walk downhill. There was really not much other choice. We were staying most of the way up the hill that Porto is built on and our first destination in the city was on the south bank of the Douro River. Which is decidedly not at the top of the hill.
The journey down the hill to the Douro is quite the walk. In most places the hill seems to go about straight down. It is so steep in most spots that paving the path with a sloped surface from point A to point B won't work. Switchbacks and curves and lots and lots and lots of steps are required. And big steps too. Walking down is an awesome voyage of discovery combined with a pretty good workout. But at least it's down. And luckily there are plenty of mechanical contraptions to get you back up to the top on the way back. Thank goodness.
As we made our way down to the Douro while keeping an eye or two firmly on where we were stepping, we caught glimpses of the river and Vila Nova de Gaia on the south bank, home to the region's many Port cellars. And if we were pointed in the right direction at the right time on our trip downhill, we could see pieces of a very large metal arch bridge: the Dom Luís I Bridge.
The Dom Luís I is one of six bridges spanning the Douro connecting Porto to the south side of the river. There are a number of boat tours which leave from the north and south banks of the river that will take you to see all six up close. But the Dom Luís I is one of the best you'll see on that tour. And you don't need to get on a boat to experience it.
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| First sighting of the Dom Luís I Bridge, Porto. |
The Dom Luís is a pedestrian, automobile and Metro bridge. The top deck is reserved for the Metro and pedestrians, and the lower level accommodates automobile as well as more people on foot. The bridge itself is an iron arch supported from massive concrete piers on either end with vertical iron trusses extending upwards from the arch to support the upper deck and downward to support the road and sidewalks of the lower level.
Its importance to both Porto and Vila Nova de Gaia cannot be understated. It is THE main thoroughfare allowing people whether on foot, Metro or car to cross the Douro River and get from one side to the other. Each time we crossed it (four times, if you must know) it was packed. I'm sure a ton of those people crossing were tourists like us but I'm guessing there were a fair number of locals also.
But it is not just functional. The bridge is also visually stunning. Not only is it sort of a true expression of its own structure with the clear span arch so obviously supporting the two decks via the connecting trusses, but the top deck is also narrower than the roadway, which causes the arch to pinch at its top and splay out towards the concrete piers. It's impossible to notice this in elevation; the bridge just seems the same width for the whole span. But catch it on an oblique view and you can see the splayed arch that captures lateral loads on the bridge and transfers them to the support piers. The best view of the bridge seemed to me to be from the top of the Teleférico de Gaia, or cable car, which connects the pedestrian areas of Vila Nova de Gaia to the top of the south side of the Bridge.
It's also a bit of an engineering marvel. When construction was completed in 1886, it was the largest clear span iron bridge in the world at nearly 1,300 feet across. It is a treat that this bridge is so accessible during a visit to Porto and Vila Nova de Gaia. It takes literally no extra effort to visit and interact with the bridge, which has become one of the most recognizable symbols of Porto.
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| View of the Dom Luís I Bridge from the debarkation point of the Teleférico de Gaia. |
The engineer of the Dom Luís was Théophile Seyrig, a German engineer who was all of 38 years old at the start of construction of the Bridge. I am pretty confident you've likely never heard of Seyrig. I hadn't. Not that I'm some authority on bridge designers or anything. But I have heard of his mentor and former partner, Gustave Eiffel, who has a tower of some sort in Paris named after him.
Eiffel actually submitted a design for the Dom Luís but lost the competition to Seyrig. But Eiffel also has a bridge that spans the Douro also and it looks remarkably like the Dom Luís. Only better. His bridge is the Maria Pia Bridge.
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| First sighting of Gustave Eiffel's Maria Pia Bridge. |
Like the Dom Luís, the Maria Pia is an iron arch with vertical iron trusses extending upwards from the arch to support the deck above. When it was built, the Maria Pia was the largest clear span iron bridge in the world at 525 feet. Or in other words, both bridges have pretty much an identical form and both pushed the limits of clear span engineering when they were built. And, like Seyrig, Eiffel was relatively young when he designed the bridge, just 43 years old. It's not really a coincidence, right?
Eiffel's commission for the Maria Pia Bridge was the result of a competition run by the Portuguese Railway Company in 1875 (it was constructed from January 1876 to October 1877). The central engineering challenge of the competition was to span a river which had never before been crossed by a bridge and which was known to be completely unsuitable for bearing on the bottom of the river. Eiffel proposed a cantilever construction method to construct the bridge from either side of the river and have the two sides meet in the middle.
Now at the time of the competition, nobody really knew who Eiffel was. There was no body of work to support his construction idea or his price tag, which was a third less than any other entry into the competition. The Railway accepted his proposal, but they ran a good background check first, and kept a close eye on him during the design and construction. It's ironic considering what would come later but every engineer starts out with no experience, right?
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| The Maria Pia Bridge, seen beyond the adjacent São João Bridge. |
Unlike the Dom Luís Bridge, the Maria Pia is not in the middle of Porto. It was built for rail trafffic only and there's no really good reason why anyone would run a freight railway through the center of a city. It's a good ways up the Douro River either on foot or by boarding one of those boat tours that spend all day every day chugging up and down the River to show the tourists each of Porto's famous bridges up close and personal-like. I'm not panning these tours. We boarded a boat in the early morning of our only full day in the city and saw Eiffel's bridge just that way. Although we also saw it on the drive into the city.
We didn't spend a lot of time in Porto. Just about a day and half over two nights. Because our time was limited, my wish list had to also be limited. And it was: at least one Port cellar and laying eyes on the Maria Pia Bridge. Not the Maria Pia and the Dom Luís. Just the Maria Pia. Eiffel's bridge is better. And yes, I know I already wrote that.
It's all about the arch. Or more precisely, the support of the arch.
Both these bridges are arches which support a top horizontal truss on a series of vertical trusses. In the case of Seyrig's bridge, those trusses also run to the bottom deck hung from the arch. But whereas Seyrig's arch is thinnest at the center span and highest point and thickest at the supports on either side of the River, Eiffel's is not. His arch is thickest at the top and center and tapers to a point at the two sides where it connects to solid ground.
Seyrig's arch terminates at a buttress. Eiffel's ends in a point or pin connection. The overall effect of the Dom Luís is one of solidity. The overall effect of the Maria Pia is lightness. And it all comes down to the supports.
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| The support of the Maria Pia at the north side of the Douro. |
It's this lightness (the pin connection does not transfer moment to the supports on the banks of the river) that makes Eiffel's bridge more pleasing to my eyes and why it, and it alone among the six bridges spanning the Douro, was one of the two reasons I wanted to visit Porto. Quite frankly, I find Eiffel's bridge almost in defiance of gravity and absolutely breathtaking. It is for sure well worth the visit to Porto and a quick boat trip down the River, as ephemeral as that experience turned out to be.
I've been to Paris three times and have laid eyes on the Eiffel Tower in that city on all three trips and find the Tower to be overly heavy and a little clunky. I didn't get that from the Maria Pia. I have not sought out many of Eiffel's works (the structure supporting the Statue of Liberty doesn't count) but I might based on this experience. This bridge truly is remarkable, even if it is difficult to get to. Definite top five bridge ever for me (and I'm honestly not sure what the other four would be so I'm guessing a little bit here). Go to Porto. Eat sardines in a riverside cafe. Drink some Port. And go see these bridges. But especially Eiffel's.
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| The Dom Luís looking south towards Vila Nova de Gaia. |
How We Did It
It is super easy to see and cross the Dom Luís I Bridge. It is pretty much one of the central focuses (or foci, I guess) of the pedestrian experience along the Douro River in Porto and Vila Nova de Gaia. We crossed the bridge the first three times on the sidewalks of the road on the bottom deck and then took the cable car to the upper deck on our fourth and final passage. I recommend you cross it on both decks for the full experience. The cable car stops running at 6 p.m. although if you are in line with a ticket at that time, you are guaranteed one way passage.
The Maria Pia Bridge is more difficult to get to. We took a boat operated by Tomaz do Douro, who got us there just fine. There is no bad seat on the upper deck of the boat where we sat the entire time. The bridge is no longer used for rail traffic. As best I can tell from searching on the internet (always dangerous, I know...), it appears the bridge either wasn't designed or constructed or maintained (not sure which) to accommodate rail travel at a reasonable speed long term. And yes, I get the irony of a bridge which looks super light not being able to accommodate the purpose for which it was built. It still looks incredible.
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