Unclassified Roads

highway = unclassified:

This classification is used for minor public roads typically at the lowest level of the interconnecting grid network. Unclassified roads have lower importance in the road network than tertiary roads, and are not residential streets or agricultural tracks. Unclassified roads are considered usable by motor cars.

Tip: if a minor roads is not a residential street or agricultural track, then mark is as an unclassified road.