Wednesday, November 20, 2019

SearchResearch Challenge (11/20/19): Where'd the river go? What's the logo?

Travel is always surprising.  

At least it is to me.  I go somewhere, and I usually find myself asking WHY questions.  I know I must sound like a 6-year oldwhy...why...why...why but those questions often lead to fun adventures, and I definitely get my curiosity scratched in the process.  

Last week I was in Seville, Spain to give a talk at an educational conference (ICERI, for the curious).  I did all of the usual tourist thingsa visit to the cathedral, walking through the narrow streets, a visit to the glorious Plaza de España and the Parque Maria-Luisa.  

But among all of the glories of Andalusian Spain, I noticed two things in particular that I had to go look up, and I thought you might find them interesting.  

As is my habit, I went for a run near the hotel.  As it turns out, the hotel I was at is right next to the Guadalquivir river.  Here's the path I took from the hotel...  

If you look carefully, you'll see that the river has two branches--a pale green one running straight, nearly due north/south, and another part that's dark green.  

It's pretty clear that the curvy part used to be the original path of the river, while the pale green section is a channel that was added.  

But what surprised me on my run was to see that the dark green river apparently used to connect to the pale green river.  When I got to the northern part of my run, it was pretty clear that the river was cut off at some time in the past.  If you go to this location on Google Maps you can easily see that this is a bit of geo-engineering.  Someone at sometime cut off the river.  Why?

And this leads me to our first Challenge of the week: 

1.  What's the story here?  When was the dark green river cut off from the pale green river?  Can you figure out when this happened?  How about WHY it happened?  What was the city hoping to accomplish?  

If you look carefully at the above image you'll see that I was running towards the "Huevo de Colon" statue.  If you remember, we actually talked about this moment in history in this blog, way back in 2012 when we were looking for a phrase that captured the idea of a problem that seems impossible, but actually has a simple answer.  The answer was "The Egg of Columbus."  This statue is Seville's monument to that story.  

But on the way there I also noticed something that I couldn't explain and HAD to look up when I got back to the hotel.  I kept seeing a particular logo on many of the city pieces of infrastructure.  It's looks like NO8DO, but not quite that.  Here's a collection of those logos: 

As you see, the "8" symbol isn't just a numeral 8.  

Here's a beautiful version of the logo as it appears on Christopher Columbus's tomb in the Cathedral: 

I saw this logo everywhere in Seville... but what was it trying to tell me?  

2.  What is the story behind the NO8DO logo?  Why does it appear everywhere in Seville--from a tomb in the cathedral to lampposts downtown, on sewer covers, and even the tops of bollards?  

Can you figure these two little Challenges out?  

As always, let us know what steps you took to come to an understanding.  

Search on!  


  1. As often is the case, the 2nd question is easier than the first. This really was the case this time as part 2 took under a minute. I chose the image of Columbus's tomb and did a reverse image search. Lots of good results e.g. - item 6.
    "Visitors to Seville will notice a symbol on many signs around the city, from taxis and buses to sewer covers, consisting of the letters ´NO8DO´. This is the city´s logo, and legend says that it originates from the 13th-century coat of arms awarded to Sevilla by King Alfonso X the Wise. He bestowed it in gratitude for Seville´s support in his battles against his son, Sancho IV of Castile, who wanted to usurp his father´s throne during the Reconquest. Between the ´NO and ´DO´ is an 8-shaped bundle of wool (madeja in Spanish). Add the three together, speaking in Seville´s fast, elliptical accent and you have ´no-madeja-do´, more correctly, ´no me ha dejado´ which means ´it (the city) has not abandoned me´. The motto was his reward to the people of Seville for their loyalty."

    Part 1 however took much longer - partially due to an assumption I'd made that this was old. It's not. It dates to preparations for Expo 92 Seville. After a bit of searching on the river and looking at the Google map, I had a 2nd look at the Wikipedia page - and saw the map This names the area as Tapon de San Jeronimo. Searching for that and variations (e.g. "Tapon" "San Jeronimo") eventually gave an article on developments for Expo 92 at

    Adding in Expo92 got me a diagram of how things had changed over the years.
    Following up the source of this - thank goodness for Google Translate - gave me this that explains it all.ón-anterior-a-la-expo-92/

    Essentially a previous damn known as Champina's Plug was moved North and a channel was made to redirect the river in 1987. The am was to protect Seville from flooding and facilitate an area to build and develop for Expo 92.

    1) Look at diagrams - and potentially use these for searching (either the diagram itself and/or text on the diagram). In this case, searching for similar diagrams or the wording got to the site.
    2) Don't be scared if a page is not English. Just use Google Translate (or similar) and search that way.
    3) Reverse image searching is also a key skill.

    1. Thanks, Arthur. Excellent job. (I quoted you extensively in my answer!)

  2. About Dr. Russell's Keynote Conference in Seville. The Joy of Search: Augmenting intelligence by teaching people how to search. We will enjoy it very soon on ICERI's YouTube Channel

    First quick approach in this week Challenge:

    For Q1 of this Challenge, thought searching first on Earth from Space by ESA (awesome weekly videos they made about our Earth and that I discovered when Dr. Russell mentioned comet years ago.

    [ Earth From Space Seville]

    Video shows the river redirected

    "Seville is located on the Guadalquivir river. While the original course of the river is visible snaking through the city on the right, we can see where water has also been redirected in a straighter course on the left.

    About the logo (Q2), searched [infinito logo Sevilla]

    Wikipedia: NO8DO is the motto and logo of the City Council of Seville

    2011: La leyenda sobre el origen del NO∞DO Legend about how was created

    Searching in English: [Seville infinite logo]
    Since1995, the NO8DO in gold with burgundy or crimson background forms the flag of Seville.

    1. Looking for more about Q1, searched:

      [Sevilla Guadalquivir cambio]

      Así domó Sevilla al Guadalquivir
      Cuando el Guadalquivir pasaba por la calle Sierpes

      [Seville Guadalquivir river change]

      The beautiful European river you've probably never heard of

      Searching with same query changing only words (adding, removing) like flow, changes and looking for the Spanish word cauce del río (I am sure is not channel as found translating others found

      The Lost Rivers of Seville

      Then tried [Seville river channel change] also added word timeline. Also trying [Guadalquivir river history]

    2. Thanks for the ESA video. I hadn't know about them!

  3. I found myself taking a similar approach to Arthur's.

    Part 1: I wanted to know when the river changed so I went into Google Earth's Timelapse (, flew to Seville, Spain, and pressed play. I saw the river jam up around 1992, so I did a quick search of "Seville Spain 1992 events" which returned the Expo92, which mentioned the river Guadalquivir. I clicked on that and came across the following image:

    With that, I did a general search for "cauces del guadalquivir abandonados" and landed on the Spanish page for "Dársena del Guadalquivir" yielding the history that can be translated into English if you can not read Spanish, which I can.

    Wikipedia said "With the works of the Universal Exhibition of 1992 he reopened the plug Chapin, moving its end farther north, to the area of San Jerónimo" which I was able to verify via the NYT:

    "Even regular visitors to Seville may be surprised by the changes. The Guadalquivir River, which was redirected to reduce flooding in the 19th century, leaving only a canal in front of the city, now again flows through Seville. Railroad tracks have been removed to turn a four-mile stretch of river bank into landscaped gardens and promenades."

    Part 2: I simply searched "christopher columbus no8do" and found the answer "The key to the puzzle lies in the central number eight, said to resemble a skein of yarn (and yes, I had to look up “skein” – it’s a loose coil of yarn or wool, the sort my grandmother used to buy for her knitting.)The Spanish word for this is madeja, so the sentence becomes no madeja do. This makes as much sense as standing in front of a charging bull, until you realise that it sounds like no me ha dejado. She has not abandoned me." at

  4. 2)
    [seville logo arms shield no8do] finds
    Wherein all is explained. Such as the 8 represents skein of yarn--I even guessed this. The nodo bit is also explained.

  5. 1) I saw in GooEarth that the place you are on is called Isla de La Cartuja. A search for this name finds in Wikipedia under Isla de La Cartuja that this was an island til 1992 when it was joined to the mainland to prvide access to Expo 92 the 500th anniversary of Chris Colombus sailing venture. At the same time the river was straightened out. So the former island which was the site for the Expo is no more.

  6. peripheral search…
    …looks like your bollard - you cropped? found from image search
    from this fall…
    the image
    tried Yandex, for grins…
    yandex symbols…

  7. Deb and Anne here. We started with Q1 and really struggled with this one. We searched and came up with dead ends. We may come back to this. Thought Q2 would be harder but found this very easily. Searched for no do symbol in sevilla meaning and got to this site which explained the connection with the symbol "King Alfonso X the Wise. He bestowed it in gratitude for Seville´s support in his battles against his son, Sancho IV of Castile, who wanted to usurp his father´s throne during the Reconquest. Between the ´NO and ´DO´ is an 8-shaped bundle of wool (madeja in Spanish). Add the three together, speaking in Seville´s fast, elliptical accent and you have ´no-madeja-do´, more correctly, ´no me ha dejado´ which means ´it (the city) has not abandoned me´. The motto was his reward to the people of Seville for their loyalty." Found many other sites that had same explanation and also found same in Wikipedia article. Now we will go back to Q1. Posting this here for now.