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non-highway road; toll-free road; local road
road shadowed by trees, mountain, etc.
高速を避けて下道で目的地に向かった。
We headed to the destination via local roads, avoiding the highway.
下道は渋滞が少なくて快適だった。
The local road had less congestion and was comfortable.
下道を通れば景色を楽しめる。
If you take the local road, you can enjoy the scenery.