The old road numbered the RD724 skirted the Foret de Paimpont crossing the River Aff.
It then headed across moorland (Camp de Coëtquidan-St-Cyr) before passing through the village of Campénéac before reaching the town of Ploëmel.
Thereafter the old route of the road is numbered the RD724 which has several steep inclines and descents as it crosses the River Evel and heads through the town of Baud.
The old and new routes then run parallel past the village of Languidic and entering the valley of the River Blavet.
The old route headed through Hennebont crossing the river and then into north west Lorient as the Rue Jean Jaurès ending eventually at the Pont de Camel and the entrance to the port.