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Although it began as a bi-monthly, it was monthly for most of its existence. Size also varied, from bed-sheet size to regular pulp size.
Prominent authors who had work published in Fantastic Adventures included Edgar Rice Burroughs, Nelson S. Bond, Edmond Hamilton, Robert Bloch, Don Wilcox, August Derleth, Rog Phillips, Theodore Sturgeon, Walter M. Miller, Jr., Fritz Leiber, L. Sprague de Camp, and Ray Bradbury. Frequent illustrators were Virgil Finlay, J. Allen St. John, Frank R. Paul, Harold McCauley, and Malcolm Smith.
The magazine merged with the digest-sized Fantastic with its May-June, 1953, issue, but then the name was dropped. Although also edited by Howard Browne, Fantastic (1952-1980) cannot be considered an extension of Fantastic Adventures.