What do black bordered direction signs primarily indicate?

Black bordered direction signs are primarily used to indicate non-primary and local routes. These signs serve to guide drivers along less significant roads that may lead to local destinations, small communities, or scenic byways, rather than directing traffic on major highways or primary routes. Their design helps differentiate these local routes from major highway directions, which often utilize different colors and styles to delineate importance.

In contrast, signs indicating primary route destinations are typically marked with different colors to signify their status as more significant routes. Emergency service locations and highway rest areas would also follow unique signage conventions to ensure they are easily recognizable and understood. Knowing that black bordered signs relate specifically to local routing allows drivers to understand their relevance in navigating smaller, potentially less-traveled roads.