A cellular telecommunications network provides a location information service. A landmark location server (11) has an associated data store (12) of data concerning location information associated with individual cells of the network. The server (11) is responsive to a request for location information from a mobile station (MS1). The request is sent as a SMS through the network (PLMN1). The server (11) obtains location information from the data store (12) based on the cell (C1) occupied by MS1 or another mobile station (MS2). The network is configured to send the location information as a SMS to the mobile station (MS1) that requested the information, without having to pre-register the mobile station for the location information service.