During mountain driving, which factor is NOT relevant when selecting speed?

When driving in mountainous areas, it is essential to consider various factors that influence safe driving speeds. One of those factors is road conditions, which can affect traction and braking ability. The gradient of the mountain is also critical, as steeper grades necessitate slower speeds to maintain control of the vehicle. Length of the mountain can impact fatigue and the duration of safe driving practices, further influencing speed selection.

City traffic regulations, however, are not directly relevant in the context of mountain driving. These regulations usually pertain to urban settings and may not apply in rural or mountainous areas, where different safety considerations and environmental conditions take priority. In the mountains, the focus should be on the specific driving conditions present in that terrain rather than urban speed limits or regulations. Thus, among the factors listed, city traffic regulations do not impact the selection of speed during mountain driving.