1. A vehicle position estimation system, comprising a device that estimates a position of a vehicle using a characteristic object included in an image that is captured by an image capturing device mounted to the vehicle, and a server that is connected to that device via a network, wherein: the server comprises: a first control unit; a first storage unit that stores landmark information, that is information related to an image of a characteristic object; and a first communication unit that transmits the landmark information to the device via the network; and the device comprises: a second communication unit that receives captured image information, is that is information related to an image captured by the image capturing device, and also receives the landmark information from the server via the network; a second storage unit that stores the landmark image information; and a second control unit that executes: recognition processing in which information related to an image of a characteristic object included in the captured image information is recognized based on the landmark information stored in the second storage unit; position estimation processing in which the position of the vehicle is estimated based on the information related to an image of a characteristic object that has been recognized; and landmark information selection processing in which the landmark information used in the recognition processing is selected from the second storage unit based on a recognition evaluation value that represents ease of the recognition processing successfully performing recognition for each item of landmark information.