Where must you be prepared to encounter sudden fog?

The combination of locations near rivers, marshy areas, and lakes is important because these environments are often prone to sudden changes in weather conditions, including fog. In Germany, drivers need to be especially cautious in these areas as visibility can drop sharply, posing a significant risk for accidents. The relevant traffic regulations emphasize staying alert and prepared for rapid weather changes when driving in such locations. Recognizing all three environments as potential fog-prone areas helps ensure safer driving practices and enhances a driver's awareness of their surroundings.