When must you stop at a railroad crossing?

Stopping at a railroad crossing is crucial for ensuring the safety of both drivers and pedestrians. The correct answer highlights the clear indicators for when a driver must stop. When lights are flashing or a train is approaching, these signals are definitive warnings that a train is either on its way or about to cross the path of vehicles. Trains travel at high speeds and can be closer than they appear, hence it's essential to take these signals seriously.

Approaching trains may not always be audible, especially at great distances or if there are environmental noises, which makes solely relying on hearing a train whistle insufficient for making safe decisions. Similarly, a stop sign does not apply to all railroad crossings since some may not have signage at all, further emphasizing the need to heed visual signals like flashing lights.

By recognizing the importance of stopping when lights are flashing or when a train is perceived to be coming, drivers can ensure their safety and the safety of others at railroad crossings.