Embodiments described herein are concerned with system for identifying an aerial vehicle. The system comprises: a radar sub-system, the radar sub-system comprising at least one radar connectable to a static support member and a transceiver configured to transmit data indicative of one or more targets identified by the radar within an airspace; a receiver arranged to receive the data indicative of one or more targets identified by the radar; and a processing system configured to process said data, whereby to identify at least one aerial vehicle. In some embodiments the radar comprises a marine radar.