The present disclosure relates to location and communication systems that can be utilized for locating cargo containers using tags with a radio communication subsystem in the form of a transponder or micro-transponder. Each cargo container tag (CCT) is capable of communicating with either other cargo container tags or a base-station (BS) locator devices. The tags can be arranged for tracking the opening and closing of doors on individual cargo containers using radio communication methods. Lost cargo container can be located using communications from a base station and the cargo container tags. CCT devices can also detect intrusions and/or tampering with cargo containers, and store a variety of collected data for later retrieval.