Buckeye Lake was once a large wetland complex, called the “Great Swamp” that was to be turned into a reservoir to feed the Ohio and Erie Canal system. The plan however didn't work because the reservoir was too shallow to feed the canal for barge traffic especially during the dry season. Strangely enough, it was the impoundment of the swamp in 1830 which made Cranberry Bog so unique.
As the waters backed up behind the dike, all of the big swamp was inundated and destroyed, except the very youngest and therefore most buoyant segment of the bog mat. Instead of disappearing beneath the mucky waters, as did most of the adjacent swamp forest, a 50-acre upper segment of the bog mat along the north shore stretched and expanded like a giant waterlogged sponge and rose 8 feet with the new water level. No longer did the floating bog mat surround the glacial lake as is typically the case with such bogs. Now the lake surrounds the bog mat, a unique situation.
An access permit from the Division of Natural Areas and Preserves is required to visit Cranberry Bog State Nature Preserve.