NAVIGATION DEVICE

A navigation device includes a determination means which determines whether or not to activate tunnel mode function based on characteristic data of the tunnel read from the database, a vehicle speed detected by the vehicle speed detection means and a vehicle position detected by the vehicle position detection means, and a control means which displays characteristics of the tunnel to be travelled through on a display means based on a command signal from the determination means to activate the tunnel mode function and which activates various on-vehicle devices in the tunnel mode function.