Route 100-K begins on Route de Bassin at Route Nationale 1 in Gonaïves, just south-west of where that route meets Route Nationale 5. Passing Bretagne, it travels all the way northward until Rivière Tête Source, which it parallels, passing through the village of Bassin, all the way until the Terre-Neuve town line.
The rocky route traverses the rugged Dolan section Terre-Neuve before crossing the Rivière Colombier into the the town center. The road continues up the town center, hooking a left at the Fond-Sarazin Road to parallel the Rivière Colombier through the town's second section, Bois-Neuf passing the villages of Nan Nicotte and La Cour Paletot. The road continues for about 6km to a fork where it veers left to cross the border into Anse-Rouge.
The road continues westbound, crossing the Rivière Colombier before entering the district of Sources Chaudes and passing through Anse-Rouge's first section. Here, it crosses the Ravine Mahotiere and then bears left onto Rue Saint-Joseph, which it follows for about 5km until ending in the town center of Anse-Rouge at Route 102.
|Gonaïves||Gonaïves||Southern terminus of Route 100-K|
|Gros-Morne||Terre-Neuve||0.0||0.0||RN-1 north to Ennery|
RN-1 south to Ville de Gonaïves
|Anse-Rouge||66.0||41.0||RD-102 north to Môle Saint-Nicolas|
RD-102 south to Gonaïves
|Northern terminus of Route 100-K|