STUMPHOUSE TUNNEL is located at Stumphouse Mountain Park, 125 Stumphouse Tunnel Road, Walhalla, South Carolina, about 7 miles northwest of Walhalla on Highway 28. It is easily accessible by car, with clear signage leading to the site. To see Stumphouse Tunnel, it's an easy walk from the parking lot.
NOTE: Park Entrance Fee is $5 per vehicle.
Bring a Flashlight: The interior of the tunnel is dark, and the ground can be uneven and slippery.
Wear Appropriate Footwear: Sturdy, closed-toe shoes are recommended for walking inside the tunnel.
Respect the Environment: The tunnel and surrounding park are part of South Carolina’s natural and historical heritage. Follow Leave No Trace principles to keep it pristine.
Stumphouse Park encompasses 440-acres & includes: Stumphouse Tunnel, Issaqueena Falls, the Stumphouse Passage of the Palmetto Trail, the Blue Ridge Railroad hiking trail, & Stumphouse Mountain Bike Park. The park has picnic tables & restrooms.
SOME HISTORY (more below the write up below vvv)
For almost 100 years the tunnel lay abandoned known only to some local explorers, adventurers, and ne’er-do-wells.
Then in 1950 it was bought by Clemson University, The publicly accessible part of Stumphouse Tunnel ends with a brick wall and iron gate built by Clemson University when they used the tunnel to make Blue Cheese.
Researchers had discovered that the tunnel’s continuous temperature of 56 ° & high humidity (the temperature inside the tunnel is a consistent 56 ° with 85% humidity year round) provided the perfect conditions for curing Blue Cheese, so in 1953 students from Clemson became the first people to successfully age Blue Cheese in the South.
This is an Earthcache!
An Earthcache is a special type of geocache where there is no container to find.
Instead you are looking for unique geological features of the area and need to
answer questions and/or posting a photo to your log in order to claim the find.
IN ORDER TO COMPLETE YOUR FIND OF THIS EARTHCACHE: DO AT LEAST ONE OF THE FOLLOWING QUESTIONS/TASKS: Please visit the site & answer the following questions based on your observations. Send the answers to me in a message or email through geocaching.com (OR POST a PHOTO TO YOU LOG IF DOING THE PHOTO OPTION) The SAME DAY YOU LOG YOUR FIND is preferable:
Questions for Cachers To log this EarthCache:
1. Color Variation: Look for color variations you see in the granite. What minerals might be responsible for the bluish hue? ________.
2. Texture Observation: Examine the granite closely. Is the texture fine-grained, medium-grained, or coarse-grained? _____
3. Mineral Identification: See if you can identify at least one of the minerals present in the blue granite, and how does this mineral contribute to the rock's appearance?. ________.
4. Observe the water dripping from the ceiling. What is one geological factor that contributes to this phenomenon? ________.
5. Post a photo (of you and/or your group if you wish) at the falls area, preferably with your GPS in the shot. THIS MAY BE USED AS ONE OF YOUR ANSWERS/TASKS.
******NOW FOR THE EARTHCACHE*****
Stumphouse Mountain Tunnel runs through solid Blue Granite with inside tunnel cuts made by hand using hand drills and sledge hammers!
GRANITE is a coarse-grained, light-colored, plutonic, or intrusive igneous rock (INTRUSIVE rock is formed when magma (MAGMA is molten rock material under the earth's crust, from which igneous rock is formed by cooling) penetrates existing rock, crystallizes, and solidifies underground to form intrusions (IGNEOUS rock is composed mostly of quartz, alkali feldspar, and plagioclase (PLAGIOCALSE is any member of the series of abundant feldspar minerals usually occurring as light-colored, glassy, transparent to translucent, brittle crystals). It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground.
Stumphouse Tunnel offers a unique opportunity to explore the geology of the region. The tunnel was intended for the Blue Ridge Railroad in the 1850s but was never completed. The site exposes an impressive face of Blue Granite, a distinctive type of granite notable for its fine grain and bluish hue.
This EarthCache will guide you through the geological history and features of the blue granite visible within the tunnel.
Geological Background:
BLUE GRANITE is technically a type of granodiorite (an intrusive igneous rock similar to granite but containing more plagioclase than potassium feldspar) formed from the slow crystallization of magma deep within the Earth's crust. Its blue coloration results from a combination of quartz, feldspar, and biotite minerals. The blue hue often comes from the presence of sodic plagioclase feldspar combined with light reflection off microscopic inclusions within the mineral structure.
The granite at Stumphouse Tunnel is part of the Appalachian geological province, specifically linked to the Brevard Zone, a major fault zone within the Blue Ridge Mountains and linked to their formation. It formed during the Taconic Orogeny around 450 million years ago when ancient continental plates collided forming the supercontinent Pangaea and causing regional metamorphism and granite intrusions. The intense pressure and slow cooling allowed medium to large mineral crystals to develop, giving the granite rock its medium-grained texture.
Key Geological Features:
Mineral Composition: BLUE GRANITE is primarily composed of:
Quartz: The most abundant mineral on the earth's surface, it is a form of silica, or silicon dioxide (SiO2), occurring in hexagonal crystals. Here the quartz is a clear to gray mineral giving the rock its speckled appearance.
Plagioclase Feldspar: A bluish-white mineral responsible for the blue tint.
Potassium Feldspar: A pinkish mineral scattered throughout the rock.
Biotite: A black, plate-like mineral contributing dark specks.
Texture: The fine- to medium-grained texture indicates a relatively slow cooling rate deep within the Earth's crust.
Jointing and Fractures: The Tunnel walls reveal natural joint patterns and fractures formed by tectonic forces and exacerbated by excavation. These fractures also allow water infiltration, contributing to water seepage, dripping water and weathering.
Weathering: Chemical weathering is visible where the granite has oxidized, producing a lighter, sometimes rusty appearance.
Educational Note: Granite is widely used in construction due to its durability and aesthetic appeal. Blue granite, in particular, is valued for its unique color and fine texture. The tunnel provides a rare opportunity to see this stone in its natural, unpolished form.
SOME MORE HISTORY:
Construction on Stumphouse Tunnel began in the 1850s as part of an ambitious project to create a rail line connecting Charleston, South Carolina to Knoxville, Tennessee. This line, known as the Blue Ridge Railroad, was intended to bypass the Appalachian Mountains, making trade and travel more efficient.
The work was grueling and relied heavily on immigrant labor, particularly Irish workers. They used black powder, hand drills, and brute force to carve out the granite. Money eventually ran out and the outbreak of the Civil War in 1861 sealed its fate, and the project was abandoned, leaving Stumphouse Tunnel incomplete.
Today, the tunnel stands as a testament to the engineering challenges of the era and remains a unique historical site. Since only part of the planned 5600 feet of the tunnel were competed, there’s no exit to the other side of Stumphouse Mountain. So you can’t walk all the way through the tunnel, but you can walk most of the completed section.
I hope you have enjoyed your visit to Stumphouse Tunnel and come away with a new understanding of how geology helps form our beautiful world.
| I have proudly earned the Geological Society of America's highest level: |
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FTF Honors Go To . . Blueyes1958!!!