The Couesnon Valley

Departure
Park in the lot at 48°18.425N 001°25.976W. Take note of the crêpe place - you'll deserve a little reward when you return. When you RETURN...!
As you leave the parking lot, cross the road and "Welcome to the Couesnon Valley, on behalf of the Conseil Général."
 
1st Riddle
Walk to 48°18.444N 001°25.942W. You'll run smack into a wash house. How many feet support the roof of this wash house? Write this number down as A - this number will be useful in calculating the final coordinates of the cache.
 
Follow the trail to the next milestone. 
 
1st Milestone 
At 48°18.549N 001°25.932W, you cross the road - continue along your path.
 
2nd Milestone 
At 48°18.707N 001°25.854W, where the trails cross, leave the left-hand path and head east, taking the footbridge that crosses the Couesnon.
 
3rd Milestone
At 48°18.761N 001°25.732W, 200 meters after the footbridge, turn left and cross the road in the direction of the rock climbing site.
 
2nd Riddle
Stop at 48°18.779N 001°25.762W. You should see a sign that says "Bienvenue à Saint-Ouen."
How many services are represented on the sign with black and white pictures? This number (between 10 and 20) will be the letter B in the final coordinates of the cache.

Head down the trail towards the Couesnon and plunge into the underbrush.

4th Milestone
GPS coordinates: 48°18.918N 001°26.353W
At this point, take the footbridge across the stream and continue along the trail until you reach the bridge that straddles the Couesnon.

When you arrive at this footbridge, cross the river and follow signs for "Belvédère."

5th Milestone
GPS coordinates: 48°19.129N 001°26.939W
At the fork in the road, head east, following the Couesnon.

6th Milestone
GPS coordinates: 48°19.104N 001°26.881W
Take the right-hand trail that heads uphill (follow the red and white GR hiking trail).

3rd Riddle
GPS coordinates: 48°18.993N 001°26.641W
You have arrived at the top of the valley. Count the number of directions indicated on the arrows on the post. This number will be C in the final coordinates of the cache.

Now strike off in the direction of St-Aubin du Cormier, continuing to follow the GR trail.

4th Riddle
GPS coordinates: 48°18.835N 001°26.400W
After you've soaked in the vista of the Couesnon Valley, take a close look at your surroundings and count how many posts support the railing of the belvedere. This number will be the letter D in the final coordinates of the cache.
 
The Cache
You will find the treasure at 48°B .8A5 N 001°26. CD5 W, near the belvedere. And enjoy the scenery!

Return
Return to the parking lot by following the GR trail eastward.

After the granite benches, leave the trail and turn left to head down toward the Couesnon - follow signs for "La ville Olivier 10 mn."

When you arrive, let yourself fall into the trap and take advantage of it to slake your thirst and, why not?, savor a tasty crêpe. You've certainly earned it!