The Tennessee River Gorge, 27,000 acres of land carved through the Cumberland Mountains by 26 miles of the Tennessee River, is one of the most unique natural treasures in the Southeast. It is the only large river canyon bordering a mid-size city and is the fourth largest river canyon east of the Mississippi. The scenic terrain of the Tennessee River Gorge creates a unique diversity of land forms. The land provides habitats for more than a thousand varieties of plants, ferns, trees, grasses and flowers as well as a rich wildlife population. Many of these are rare or endangered species such as the Mountain Skullcap and birds like the Osprey and Bald Eagle. Dozens of archaeological sites bear evidence of man's presence in the Gorge for thousands of years. Before construction of TVA's system of main river and tributary dams, Chattanooga was the site of some of the most devastating floods in the nation. At this point on the river, called the "Grand Canyon of the Tennessee," a steep, narrow gorge severely restricts the flow of the river. The restricted flow increased the severity of flooding. Chickamauga Dam, located upstream from Chattanooga, and Nickajack Dam, located downstream from Raccoon Mountain, allow TVA to control the flow of water through the gorge. During periods of heavy rainfall water can be regulated in the reservoirs, greatly reducing the threat of flooding at Chattanooga.
The Southern Appalachian Mountains span a vast area from Virginia to Georgia, and are some of the oldest mountains on Earth. Molded and shaped by volcanism, erosion, glaciation, and other geologic forces, these mountains are known worldwide for their unusual beauty and rich biological diversity.
This area is primarily composed of sandstone. Here the Tennessee River has carved into the sandstone and sedimentary rock 1200 feet creating this breathtaking gorge you will see.
Closer examination by air or topographical maps give clues to a very interesting story on how the Tennessee River Gorge was formed. Prior to its course through the gorge the Tennessee river meanders 75 miles south through the wide open valley before turning around Moccasin Bend and then abruptly turning and entering the narrow gorge whose walls rise upward for a thousand feet.
Why does the river leave the easy grade of the old established valley to enter a youthful gorge cut in solid rock?
It is believed that the river did not always follow this course, but instead flowed serenely southward to the sea past Missionary Ridge and Lookout Mountain, before joining the Coosa; its course was comparatively straight. Likewise nearly twenty miles to the northwest the Sequatchie river flowed southward in the Sequatchie valley.
At an early date a west-flowing tributary to the Sequatchie began to cut a narrow gorge into the high plateau. Slowly it cut its channel downward and extended its headwaters eastward. Finally the tributary cut through the plateau and tapped the waters of the Tennessee. Since its valley offered a quicker escape to a lower level, the Tennessee was diverted to its present tortuous course through the newly made gorge. The old valley south of the point of diversion was left with but a trickle of water flowing southwestward to the Coosa.
To log and get credit for this cache you need to observe three informational plaques at the coordinates which are at a overlook site. Email me the title on each of these three plaques.
Geological information - http://www.cr.nps.gov/history/online_books/regional_review/vol2-6b.htm
Plant Species in the gorge - http://www.trgt.org/plant.htm
