IN-VEHICLE DEVICE, AUTOMATICALLY DRIVEN VEHICLE, AUTOMATIC DRIVE ASSIST SYSTEM, AUTOMATIC DRIVE MONITORING DEVICE, ROAD MANAGEMENT DEVICE, AND AUTOMATIC DRIVE INFORMATION COLLECTION DEVICE

An autonomous driving display system (3999) includes: an autonomous driving control device (3300) to carry out autonomous driving; an autonomous driving display device (3900) display state of which is recognizable from outside a vehicle (3000); and an in-vehicle device (3500) to make the autonomous driving control device (3300) carry out autonomous driving of the vehicle (3000) upon receiving an autonomous driving instruction signal instructing autonomous driving, monitor start of the autonomous driving of the vehicle (3000) by the autonomous driving control device (3300), and control a display state of the autonomous driving display device (3900) to be in a display state different from a display state before the autonomous driving is started when the autonomous driving of the vehicle (3000) is started by the autonomous driving control device (3300).