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Geek Weekend (Paris Edition), Day 3: The Arago Medallions

The old Paris Meridian (which was in use up until 1914) passes not far from The Pantheon which I visited to see Foucault's Pendulum. It's actual longitude today is 2°20′14.025″.

To mark the old meridian the French decided to install some art work and they commissioned an artist called Jan Dibbets to build something appropriate. What he did was embed brass disks in the streets of Paris marking the meridian and turning the whole city into a sort of treasure hunt.

These Arago medallions (which celebrate the meridian and the life of François Arago) cut through the very heart of Paris. They make a wonderful way to see Paris at going on a treasure hunt. And the meridian goes to the very heart of something important: the meter. The original definition of a meter was based on the length of the Paris meridian from the north pole to the equator. Arago surveyed the meridian and came up with a very precise definition for this fundamental unit of measure.

Here's a photo I took of one on Boulevard Saint-Germain:


There's a full list of the medallions (in French) here. And here's my English translation of the list (the numbers in parentheses give the number of medallions to be found there):

Position of the medallions along the meridian from north to south

  • XVIIIe arrondissement


    • 18 av. de la Porte de Montmartre, in front of the municipal library (1)

    • Intersection of rue René Binet and av. de la Porte de Montmartre (1)

    • 45/47 av. Junot (1)

    • 15 rue S. Dereure (1)

    • 3 and 10 av. Junot (2)

    • Mire du Nord, 1 av. Junot, in a private courtyard with controlled access (1)

    • 79 rue Lepic (1)


  • IXe arrondissement


    • 21 boulevard de Clichy, on the pavement (2)

    • 5 rue Duperré (1)

    • 69/71 rue Pigalle (2)

    • 34 rue de Châteaudun, inside the courtyard of the Ministry for National Education (2)

    • 34 rue de Châteuadun (1)

    • 18/16 and 9/11 boulevard Haussmann, in front of the restaurant (2)

    • Intersection of rue Taitbout, in front of the restaurant and 24 boulevard des Italiens (2)


  • IIe arrondissement


    • 16 rue du 4 septembre (1)

    • 15 rue saint Augustin


  • Ie arrondissement


    • 24 rue de Richelieu (1)

    • 9 rue de Montpensier (1)

    • At the Palais Royal: Montpensier and Chartres Colonnades, Nemours Gallery, passageway on place Colette and place Colette in front of the café (7)

    • Intersection of place Colette and Conseil d'État, rue saint Honoré (1)

    • place du Palais royal, on the rue de Rivoli side (1)

    • rue de Rivoli, at the entrance of the passageway (1)

    • At the Louvre, Richelieu Wing: French sculpture room and in front of the escalator (3)

    • At the Louvre, Napoléon Courtyard, behind the pyramid (5)

    • At the Louvre, Denon Wing: Roman antiquity room, stairs and corridor (3)

    • Quai du Louvre, near the entrance to the Daru pavillion (1)

    • port du Louvre, not far from the Pont des Arts (1)


  • VIe arrondissement


    • port des Saints-Pères (1)

    • quai Conti, near the place de l'Institut (2)

    • place de l'institut and rue de Seine (1)

    • 3 and 12 rue de Seine (4)

    • Intersection of rue de Seine and rue des Beaux-Arts (1)

    • 152 and 125-127 boulevard Saint-Germain (2)

    • 28 rue de Vaugirard, on the Sénat side (1)

    • In the Jardin de Luxembourg, on asphalt and cement surfaces (10)

    • rue Auguste Comte, at the entrance to the garden(1)

    • av. de l'Observatoire on the pavement near the garden (2)

    • Intersection of av. de l'Observatoire and rue Michelet (1)

    • jardin Marco Polo (3)

    • Intersection of av. de l'Observatoire and rue d'Assas (1)

    • place Camille Jullian (2)

    • On the ground at the intersection of av. Denfert Rochereau and av. de l'Observatoire, on the Observatoire side (1)

    • av. de l'Observatoire (2)


  • XIVe arrondissement


    • Courtyard of the Observatoire de Paris (2)

    • Inside the Observatoire (1)

    • Terrace and garden in the private area of the Observatoire (7)

    • boulevard Arago and place de l'Ile de Sein (6)

    • 81 rue du faubourg Saint Jacques (1)

    • place Saint Jacques (1)

    • parc Montsouris (9)

    • boulevard Jourdan (2)

    • Cité universitaire, on the axis from the pavillon Canadien to the pavillon Cambodgien, the final one is behind the pavillion (10)



This special Google Map has many of them on it, the rest you'll have find by wandering:

View Paris Meridian in a larger map

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