It takes 80 minutes to drive from Preuilly-sur-Claise to Tours, a distance of approximately 75km (about 45 miles). Driving this distance involves using about 4 litres of fuel each way (at €1.40 a litre) and then paying for parking.
Imagine my delight at discovering that you can do this same trip by bus for €1.50.
You can see by the map that the bus takes a slightly circuitous route - which is why the trip takes one hour and 55 minutes. There are three buses a day from Preuilly to Tours during school term (7.00 10.20 and 17.28), two a day during school holidays (10.20 and 17.28), and four a day on the return trip.
The bus station in Tours isn't attractive by any means, but is it in front of the striking Tours central rail station.
The buses are run by Bus Fil Vert, whose website is here