The phrase "mountainous roads" refers to roads that are in or go through mountains. These roads are usually very steep, winding, and challenging to drive on because of the mountainous terrain. Full definition
I commute 34 miles one way in mountainous roads... It will chase squirrels up trees!!!! AWD awesome... wish I had a Blutec. (cars.com)
As sport bikes and slammed Miatas speed through the winding mountainous roads at blazing speeds, our all - wheel - drive MKZ holds its own, hugging corners and providing road feedback usually associated with German sport sedans from BMW AG and Audi AG. (wardsauto.com)
Brewster County students spend almost as much time on mountainous roads, catching up on sleep or homework, as they do sitting in class. (edweek.org)