Located off the north shore of Buckeye Lake, Cranberry Bog State Nature Preserve is truly a one-of-a-kind site. The world’s only island bog, it’s a remnant of Ohio’s glacial past.

Often referred to as a floating bog, Cranberry Bog’s sphagnum mat is not truly floating. The incredibly absorbent layers of peat, dead sphagnum moss, expanded like a giant, waterlogged sponge and rose 8 feet with the new water level. The resulting island was designated as a National Natural Landmark in 1968 and dedicated as a state nature preserve in 1973.

Once 50 acres in size, the bog has now eroded to less than 11 acres. Today, the bog meadows are disappearing at a rapid pace with the arrival of hardwoods and other plants.

On June 12, the division will be offering its biennial Open House offering visitors guided tours (one boat every half hour) beginning at 9:30 a.m. through 4 p.m.

Reservations are required. Reservations will be accepted for this event beginning May 11. Tours times are 10 a.m.-noon, noon-2 p.m., or 2-4 p.m.