Low altitude balloon photography, as developed by the authors, utilizes a hydrogen or helium filled blimp, attached above a camera, and tethered to the ground with polyester cordage. It can be of enormous value for mapping archaeological sites, including those underwater. Article also discusses digitized photography and recent NASA computer software that can analyze images of the earth's surfaces. Authors are presently compiling data for an Aerial Atlas of Ancient Crete, which will include digitized analysis of aerial photographs for 43 major sites. -- AATA