1. A navigation system to be installed in a vehicle, the system comprising: a memory that stores: predicted distance range data in which distance ranges where a vehicle will be within a specified time are predicted for individual zones and individual time periods; and traffic data that is created based on traffic circumstances in individual links and individual time periods; and a controller that: defines, based on the predicted distance range data and using the current time as a reference, a temporal sequence of predicted distance ranges centered at the current host vehicle position; and searches for a recommended route from the current host vehicle position to the destination among links within each of the defined predicted distance ranges, the recommended route determined by using the traffic data for the time periods that correspond to the predicted distance ranges.