It snows in Cuba?
That's sand, as seen on high-contrast, 1960's black and white film.
Go have a look at the site today. It's just to the east of the point noted on the photo (22.666°N, 83.3°W). Plug the coordinates into Wikimapia, and it will show you the outline of the base (San Cristobál I). The soil is tan-colored, sandy. The site is about 60 miles southwest of Havana. It's one of nine bases which made up Operation Anadyr.