Information courtesy of  maps.google.com

Summary:

If driving from Paris take the A10 motorway (Paris-Bordeaux),  exit at junction 25 Ste-Maure-de-Touraine. After exit head towards Ste-Maure-de-Touraine but take exit marked for Loches at the roundabout just outside town. At next roundabout (only a short distance along Loches road) take exit for D910 'Descartes' .Drive on until you reach La -Celle-Saint-Avant. At roundabout outside of town take exit to left D750 'Descartes'. Continue on this road, partly by-pass the town using the D31. Follow road in direction of Le Blanc and Le Grand Pressigny ,you will have to negotiate a few twists and turns through the town before going back onto  D750,continue on this road until you arrive in Barrou.

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