Above is what some term a "concave cave" located about a quarter of a mile behind Sherman Elementary School along Springmill Road/Ohio 39 on the north side of Mansfield.

EDITOR'S NOTE: This story is in response to a reader-submitted question through Open Source, a platform where readers can submit questions to the staff. A Richland Source reader asked, "Why are there two caves behind John Sherman School on 39?" 

MANSFIELD -- Bruce Brewer knew what boots to wear, the knee-high rubbers.

The 50-year-old head custodian at Sherman Elementary School agreed to help me answer a question Richland Source readers asked about two mysterious "caves" behind the school.

It required us to hike about a quarter-mile into a wooded area behind the school, located along Springmill Street/Ohio 39 on the north side of the city, following a trail that Brewer keeps mowed.

At the end of the trail is a set of wooden steps down into an active stream bed, steps that Brewer said the U.S. Army Corps of Engineers installed in 1977. The school was built in 1961.

Even before we started down the stairs, one of the "caves" a reader asked about was easily seen through the bare trees.  It was a big hole in the rock and I snapped a few photos.

In my jeans and hiking boots, we headed down and I gingerly cleared the last step down into the creek bed. I was immediately struck by the quiet, a silence interrupted only by the gentle sound of running water and birds chirping. It was hard to believe this kind of real nature was in the city, on the property of the 27-acre Sherman school grounds.

"This is just an awesome place. It's a beautiful sight, isn't it?" Brewer asked with a degree of pride in his voice. "I haven't been back here in five years. I love it. All we need are some trout."

creek bed

The view from a creek bed behind Sherman Elementary School.

Brewer attended Sherman Elementary before eventually graduating from Malabar High School in 1988, the next-to-last class of Falcons before the merger with Mansfield Senior. He joined the school district 29 years ago and has worked at every building.

As I took closer photos of the hole in the stone wall that rises above the creek, Brewer told me students in outdoor education classes several years ago measured it as almost four feet wide and eight feet deep.

As we hiked up and down the creek bed, we crisscrossed several places, revealing why Brewer had chosen the knee-high boots. Brewer said there are actually five such holes, though some have top ledges that have collapsed since he was last there.

A pair of Canadian geese honked overhead as we crossed at one point. I nearly slipped down a couple of times on slippery, moss-covered rock as Brewer pointed out the logging that had taken place on the other side of the creek, land not owned by the district.

While I joined him in lamenting the downed trees, it didn't detract from the abject beauty of the scene.

"Come back here next month, sit on the steps as it's getting dark. The peepers (frogs) come out ... it's an awesome song. Lights this holler up," Brewer said.

During our tour of the creek bed, the district veteran suggested two or three times that I visit nearby Springmill STEM Elementary school. He said a local artist had painted a mural on the gym walls that was based upon visiting this beautiful site. I promised him that I would do just that.

After taking photos, we headed back up the stairs and I asked Brewer if he was close to retirement.

"I can ... it kind of depends on which direction the district is headed. I don't want to. I love what I do," he said.

OUTDOOR EDUCATION: When we got back to the school, I sat down with second-year Principal Michael Brennan, who admitted he has not yet hiked back to the creek.

"I heard it's really pretty," he said. "I just haven't had the time to go back there."

Brennan said the former outdoor education program likely ended when Sherman Middle School closed, leaving only the K-3 elementary school.

"With the little ones, we have a little harder time keeping them together in the woods. It's more of a safety issue," Brennan said. "Those are the kind of things I would like to see happen ... third graders, maybe fourth. I want them to see the erosion part of it, the science part, where they can make connections with the curriculum.

"These are the things we should teach the kids. We teach them with books and videos, but we don't get our hands dirty like we probably should."

EXPERT TIME: When I returned to Richland Source, I had photos and descriptions, but still no definitive answer as to what caused the "caves." I sent an email seeking answers to Ozeas S. Costa, Jr., PhD, associate professor in the school of earth sciences at The Ohio State University at Mansfield.

Source co-worker David Yoder, an OSU alum, had suggested Dr. Costa. We could not have selected a better resource.

In his email reply, the professor said he knew that area well and used to take field trips there with students.

"Those are not caves in the strictest sense of the word (“large underground chambers usually formed by water weathering and erosion of soft rocks”) but rather overhanging ledges with concave undersurface (some call them “concave caves”), carved by an unnamed stream that is tributary of the Rocky Fork," he said.


Above is a map created by Ozeas S. Costa, Jr., PhD, associate professor in the School of Earth Sciences at The Ohio State University at Mansfield.

Dr. Costa said the ledges are carved on coarse grey sandstones from the Black Hand Formation.

“These sedimentary rocks are of coastal marine origin, and were deposited during the Mississippian Period (about 340 million years ago) when Ohio was covered by a shallow interior sea. About 15 feet of the Black Hand Formation are exposed in this area behind Sherman Elementary," he said.

"The top of the outcrop sits at 1,460 feet of elevation above sea level, and is part of the so-called Mansfield Highland, the second highest highland in Ohio," he said. "The ledges are formed by stream erosion at different water levels, as exemplified in the photo below."

water levels

About 15 feet of the Black Hand Formation are exposed in this area behind Sherman Elementary, according to Ozeas S. Costa, Jr., PhD, associate professor in the School of Earth Sciences at The Ohio State University at Mansfield. He provided Richland Source this photo. He said the top of the outcrop sits at 1,460 feet of elevation above sea level, and is part of the so-called Mansfield Highland, the second highest highland in Ohio. The ledges are formed by stream erosion at different water levels, shown in the photo.

Dr. Costa said there is not a particular name for this type of landform. He said some call them rock ledges and others call them ravines.

"The erosive process that created them is called abrasion (similar to sand blasting). These erosive landforms are very common in Ohio. In Richland County, we can find similar outcrops along Switzer Creek (Monroe Township), at the Opossum Run (Washington Township), at the old stone quarries near the State Reformatory (Madison Township), and at the Ohio State Mansfield Campus (creek behind Ovalwood Hall)," Dr. Costa said.

"Elsewhere in the state we can find similar landforms in Hanover Township (Licking County – Black Hand Narrows and Hanover village), in Eden Township (Licking County – Rain Rock), in Washington Township (Licking County – abandoned stone quarry one mile south of Utica), in Jackson Township (Knox County – along the banks of Wakatomika Creek), in Union Township (Knox County – Rocky Hollow along Kokosing River), in Pike Township (Knox County – Keller’s Rock along Little Schenck Creek), and in Hanover Township (Ashland County – along the Clear Fork of the Mohican River).

"The Lyons Falls, in the Mohican State Forest, is another example of an overhanging sandstone ledge with concave undersurface that is 50 feet high. Ash Cave, in Hocking Hills, is also another example of this feature, with 60 feet of rock exposure.

"Although the rocks were deposited about 340 million years ago, the erosion that exposed these ledges is much more recent, probably beginning around 18-20 thousand years ago, after the ice sheets retreated from this region," Dr. Costa said.

SPRINGMILL MURAL: With the tour complete and the questions answered, all that remained for my story was to visit the Springmill STEM Elementary gymnasium to see the mural Brewer had told me about. I called Principal Regina Sackman and she graciously invited me to come see for myself.

main gym

The entire gymnasium at Springmill STEM Elementary School looks like a scene from local nature.

Brewer had undersold the artwork done in 2011 by Tom Bishop, a 1978 graduate of Malabar. It took an entire summer to create.

Basically, the four walls and the floor of the gymnasium have been created to look like the scene of the creek bed I had visited a few days earlier. The three-dimensional portions of the walls are remarkably similar to the walls that rise above the stream. Twisted tree roots adorn one of the walls. Wildlife indigenous to the area are clearly visible. The floor has blue streams coursing across it.


The three-dimensional artwork in the gym at Springmill STEM Elementary School has walls that mirror those found in a nearby creek bed behind nearby Sherman Elementary School.

A student in that kind of environment can't help but marvel at local nature, which I believe was Bishop's goal, as well as the district that commissioned it. There were no honking geese or rushing water, but I felt I was back in the nearby creek bed.

I took photos, thanked Sackman and headed back to Richland Source to write the story and edit the photos.

It all began with a simple question from a reader, a query that other readers selected through an online voting round. It ended with a morning spent in the great outdoors, a great educational exchange with a professor and a visit to another Mansfield elementary school.

I trust we answered the question. And I thank the readers who asked us to answer it for them. I had a blast.

If you have a question, it may be the next one we answer. Submit your's below.

Support Our Journalism

Our content is free and always will be - but we rely on your support to sustain it.

City editor. 30-year plus journalist. Husband. Father of 3 grown sons and also a proud grandpa. Prior military journalist in U.S. Navy, Ohio Air National Guard. -- Favorite quote: "Where were you when the page was blank?"