What must vehicles on a secondary road do when approaching a through highway?

When vehicles on a secondary road approach a through highway, they are required to stop before entering or crossing the through highway. This rule is designed to enhance safety, as through highways typically have higher traffic volumes and faster-moving vehicles. Stopping allows drivers to assess the traffic conditions and ensure it is safe to proceed.

By adhering to this requirement, drivers are better positioned to make informed decisions that reduce the risk of collisions. The expectation to stop applies regardless of whether other cars are present, as conditions can change rapidly and it is always the responsibility of the driver on the secondary road to yield to the right of way conditions established for the through highway. This foundational traffic rule is essential for maintaining order and safety on the roads.