An unmanned aerial delivery vehicle acquires transfer position information indicating a position at time of package transfer of an unmanned ground delivery vehicle that receives a package in a case where a predetermined condition based on position information of the unmanned aerial delivery vehicle that transports a package is satisfied. A position of the unmanned ground delivery vehicle at the time of package transfer is identified by the unmanned aerial delivery vehicle. The unmanned ground delivery vehicle acquires delivery destination information of the package transported by the unmanned aerial delivery vehicle.