Glacial Islands

When glaciers carved out the Lake Erie basin 12,000 years ago, limestone deposits in the western basin eroded more slowly than the softer shales to the east. The western end of Lake Erie is shallower, and islands of limestone protrude above the surface. Caverns and caves are found below the water and on some of the islands, such as Crystal Cave on South Bass Island.

The limestone bedrock of Kelleys Island generates a thin, alkaline soil much different from the heavy deposits of clay that cover much of northern Ohio. In turn, the island soil supports its own kind of plant and insect life. Prickly ash, wafer ash, and hackberry trees are common on the island and host the caterpillar of the snout butterfly, which is rarely seen in the Cleveland area. Giant swallowtails appear in great abundance.

Visitors scrambling on the rocks along the water's edge may notice stones with long, semicircular grooves. The Glacial Grooves on the north side of Kelleys Island are the largest easily accessible such grooves in the world. They were scoured into solid limestone bedrock about 18,000 years ago by the great ice sheet that covered part of North America. A 400-foot-long, 35-foot-wide, and 10-foot-deep trough remains today. The ice flowed from the north in what is now the Lake Erie basin. The Devonian limestone with the grooves contains marine fossils of saltwater creatures that swam 350 to 400 million years ago. After the glacier melted, topsoil and organic matter gradually covered the grooves. Limestone quarrying in the 1830s removed much of the topsoil and exposed huge tracts of glacial striations, but this same quarrying also destroyed many glacial grooves larger than the ones exposed today.

Kelleys Island is also home to North Shore Alvar State Nature Preserve, the only undisturbed alvar community in Ohio. Formed in glaciated regions of the northern hemisphere, alvar is limestone or dolomite bedrock that remains exposed due to constant scouring by waves and ice off the Lake Erie shore. Its unique herbaceous plant life is a combination of boreal, southern, and western plants -- relics of the post-glacial environment and the warm, dry period that followed the retreat of the Pleistocene glaciers.

During the past 60 years, important shoreline habitat in Ohio has been significantly altered and degraded through the construction of cottages, marinas, docks and sea walls. Kuenle Wildlife Area on Middle Bass Island preserves a magnificent wetlands habitat, thick with vine-draped trees and wild morning glory. This serene wetlands area harbors an impressive array of plant and animal life, including many species of songbirds, wading birds, waterfowl, fish, turtles and salamanders, and the rare Lake Erie water snake. The Middle Bass Island State Park marina area consists of a large wetland complex with a Lake Erie coastal forest, emergent, shrub, aquatic bed and mudflat communities. Plant species found within this area include eastern cottonwood, willow, buttonbush, arrow-wood, silky dogwood and the only known population of American water lotus

While French fur traders were the first Europeans to "discover" the islands in the 1600s, the history of this area goes back farther. A mysterious slab of limestone known as Inscription Rock, one of the oldest and best examples of petroglyphs found in Ohio, holds many clues about the lives of the people who lived on the islands between 1200 and 1600 AD.

Early settlers, particularly those of German origin, noticed a similarity in the soil conditions and weather between the islands the grape-growing regions of Europe. Grape-growing and wine-making became major industries on the islands, and encouraged the arrival of steamboats carrying supplies and people, as well as providing transportation for barrels of wine and bushels of grape. Even as the winemaking industry suffered following the Depression, people kept traveling to the islands for their natural beauty, festivities, and the opportunity to escape. Today, the islands are best known as a mecca for boaters and vacationers.

In the 19th century, the islands' strategic location also made them the site of the Battle of Lake Erie, a turning point in the War of 1812. During the Civil War, Confederate "pirates" terrorized the islands when they seized two steamers in an unsuccessful effort to liberate the Johnson Island POW Camp. The shipwrecks that dot the waters around the islands remind us of the brute strength of the water and wind, natural forces that shaped this coastal landscape.