One-hour walk back and forth from the cottage on foot, maximum height difference 100m.
At the church, follow the road to Chambéry, turn the “chemin des Moulins”, go down to the wastewater treatment plant (to macrofites, curiosity to visit!) sign indicating green on white background “Moulin de Fontaine Froide” and “Pont du Sordet“.
Choose the path that goes down along the macrofite field: it leads under wood to the path from the Sordet Bridge, take on your rightside, pass in front of the ruins of the mill; 150 m further begins the canyoning site (remarkable photos on this web page)
For the way back, you may prefer the road (yellow above)