An information regeneration method embodied in a FORTRAN program for storing topographic maps in a digital computer in compact form. A statistical model of the terrain is used. The major outlines of the topography are entered directly. When the altitude of any point is desired, the interstices are "fleshed out" by regeneration from the probability distribution of altitude variations, thus trading computer storage for execution time. Any desired degree of realism can be achieved at increased space/time cost. If realistic representation of a particular area is needed for detailed analyses of the influence of terrain, the direct representation methods described in RM-4636 are recommended. The statistical method is preferable for broad-brush analyses, in particular for terrain variation in a Monte Carlo analysis.