A route guidance system to guide an emergency vehicle to an emergency site includes a first navigation apparatus mounted in a first emergency vehicle and a second navigation apparatus mounted in a second emergency vehicle. The first navigation apparatus performs an approach route record process which records an approach route of the first emergency vehicle from a predetermined reference position to an emergency site, and an approach route transmission process which transmits the recorded approach route upon detecting a predetermined manipulation by an occupant when the first emergency vehicle reaches the emergency site. The second navigation apparatus receives the approach route transmitted from the first navigation apparatus and performs an approach route guidance process to guide the second emergency vehicle to the emergency site based on the received approach route.