A system comprises a computer having a processor and a memory, the memory storing instructions executable by the processor to monitor a position of a vehicle while an adaptive cruise control feature of the vehicle is set to operate in a standard operation mode, identify, based on the position of the vehicle and on visibility zone information, a limited visibility zone in a route of travel of the vehicle, and cause the adaptive cruise control feature to operate in a modified operation mode while the vehicle is in the limited visibility zone, wherein during operation in the modified operation mode, the adaptive cruise control feature operates in accordance with one or more modified operating parameters.