RANDOLPH — Earl McElfresh will be he guest speaker at the Randolph Historical Meeting at 7 p.m. Wednesday in the Randolph Municipal Building.

McElFresh will be speaking on the eve of the 75th anniversary of the Allied plan to send an immense invasion force across the turbulent and uncertain waters of the English Channel and to land them on the German occupied French coast that was expectant, alert, and heavily defended. It would be the largest, most risky, complex and ambitious military operation ever undertaken. The presentation is not an account of the actual invasion itself but a detailed description of the preparations that were necessary in mapping, and intelligence terms, given the logistical and topographical nightmare that such an invasion entailed.

McElfresh will describe the where, the why and the how of the preparation of the amazingly detailed and accurate maps the Allied map-makers were able to produce of the enemy occupied coastline, an effort that resulted in maps that were crucial to the success of an invasion of Normandy that was itself crucial to ending Adolph Hitler’s “Thousand Year Reich.”