Take a look at:
http://www.bretonbikes.com/routes97.htm
If you have a Michelin road Atlas the legend shows a very thin red line as the simbol for a dedicated cycle track. There is a long one starting just out side Bordeaux on the North bank of the Gironde near Bouliac South along the river side, then allng the Pimpine to Creon before evenually reaching Sauveterre de Guyenne.
Found the one near Bordeaux by accident - wondered what the line was on the map and then looked up the Legend.
Alternatively if you google 'Cycle Routes Brittany' Stanford's have a map for sale.
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