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I’ve been looking through the Civitates Orbis Terrarum to get a sense of the way Medieval cities and their surroundings were organized, but there are some questions I haven’t been able to answer about the logistics of river trade.

Were the arches on any bridges large enough to permit river traffic to pass under them? If not, would a river boat simply ferry up- and downriver between bridges? (i.e., would goods commonly have to be loaded and unloaded multiple times along the same river?)

Is this bridge, for example, large enough to accommodate a barge? (Lincoln High Bridge, built 1160 CE) Where I’m from, they need to raise the bridges to let barges pass.

(Edited to narrow scope)

EDIT 2: Thanks to everyone who’s responded so far. I know there were some bridges clearly able to accommodate river traffic, but a river is only as navigable as the smallest bridge along its course. If there is any single bridge your boat can’t fit under, it’s an impassible barricade, no matter how many other bridges will let you pass. If they ran into a bridge like that, did they haul the barge over land? Or, per my original question, did a barge only travel as far as bridges would allow it, requiring goods to be transferred between multiple boats over the course of their transport?

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    This is too broad. Too many questions covering too large an area. – Lars Bosteen Oct 13 at 23:02
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    The overwhelming majority of river traffic is, and always has been, on barges - which easily fit under arched river bridges. – Pieter Geerkens Oct 13 at 23:31
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    Special adaptations were made in some cases to allow the river boats to lower their mast when reaching bridges, see Thames Sailing Barge: The masts are mounted in tabernacles so they can be lowered to pass under bridges – justCal Oct 14 at 0:03
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    @kenkujukebox - depends entirely on the size of the barge. Modern barges have a much larger profile than historical ones – Thomo Oct 14 at 0:04
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    If you were at all sensible, you would build your barges or boats so they fit through the arches of existing bridges. And if you were building a new bridge on a river that already had traffic, you'd size the arches to accomodate the traffic. You might look at the narrowboats that carried cargo (and still carry tourists &c) on the British canal system: en.wikipedia.org/wiki/Narrowboat – jamesqf Oct 14 at 3:39
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Why would you think that medieval people would build such impractical bridges?

After all, there are surviving medieval bridges, which are perfectly capable to allow river traffic.

Stone Bridge Stone Bridge in Regensburg, Germany from the 12th century


Edit: the OP is interested in non-navigable bridges.
There is consensus in the comments, that in terms of economy a ferry offers the benefit of not hindering river traffic while allowing for road traffic across the river. A non-navigable bridge would only allow road traffic across the river, while all goods transported on the river would need to be loaded between barges up- and down-river.
As river traffic was more economical in the past, a ferry would be the preferred solution.

So, what about non-navigable brides?

Wikipedia offers several examples of bridges, which are quite narrow (in terms of span-width).

The Anping bridge
The Anping bridge in China from the mid 12th century

The Arkadiko Bridge
The Arkadiko bridge, although I am not sure whether it spans a navigable water way.

An example of a non-navigable bridge The Tarr Steps
The Tarr Steps from somewhere between the Bronze Age and 1400 AD, yet I am not sure whether it spans a navigable water way.


Yet another topic addressing the question: un-loading and re-loading the cargo.

In medieval law there was a thing named Staple right, which forced a merchant to offer his goods in a place (city) that had the Staple right. So a trader would have to unload the cargo, and offer it on the local market for a prescribed period. Afterwards the cargo can be loaded again on a river barge.
In such a scenario, there would be an actual incentive to build a bridge with a quite narror span, as it would prevent anybody from simply passing the city.

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    Worth noting that the bridge in this picture is built such that arches rest on wide platforms which extend both along and against the water flow - one of those platforms purpose is to prevent ships from crashing into arches. – sharptooth Oct 14 at 13:07
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    I guess that another "feature" of the those prismatic platforms is to serve as ice-breaker (also referred to as Starling), at least on the upstream side. – Dohn Joe Oct 14 at 13:36
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    @DohnJoe: I expect that they also have the effect - on both upstream and downstream side - of reducing eddies in the current - again aiding barge traffic by making steering easier. – Pieter Geerkens Oct 14 at 14:10
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    Your rhetorical question has an easy answer: Because — maybe — they weren't capable of creating higher and wider arches but still in need for a sturdy bridge to allow land travel. After all this is reason sometimes pontoon-bridges are installed. – Alfe Oct 14 at 14:42
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    @Alfe Water transportation (where it is possible) has traditionally been less costly than land transportation, especially for freight. So I find your argument unconvincing. – Spencer Oct 14 at 15:02
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The old London Bridge (1209-1831) not only had arches wide enough for river traffic, it had a lifting drawbridge in the middle to allow tall ships to pass through it. It’s true, however, that the current through the arches was very rapid because of the obstruction to the river from the bridge’s structure.

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