Méridienne verte

The Méridienne verte (Green Meridian) is a project devised by the architect Paul Chemetov for the 2000 celebration in France. It involved marking on the ground the Paris Meridian crossing France from North to South (from Dunkerque in Nord-Pas-de-Calais to Prats-de-Mollo-la-Preste in Pyrénées-Orientales) by planting trees along the whole line.

On 14 July (Bastille Day) 2000, a picnic was organised along the length of the Méridienne verte. For the occasion, the imaginary line was marked in the sky above Paris by two lasers, located on the Observatory, whose centre defines the longitude of the meridian, and the nearby Senate, also on the line. With a diameter of 4 m and a reach of 1.3 km, their coloured beams lit up the 6th and 14th arrondissements of Paris for three consecutive nights, from 13 to 15 July.

At the intersection of the Meridian and the 45th parallel, in the commune of Ayrens (Cantal), trees have been planted in two perpendicular lines to mark the crossing.

From North to South, the Méridienne verte crosses 8 régions, 20 départements and 337 communes.

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