This tunnel is one of the key parts of the Katy Trail. It crosses under the Moniteau Bluffs, next to the Rocheport Trail Bridge.
The tunnel is one of a number tunnels in central Missouri. As the Ozark Mountains begin to rise up, it required tunnels to construct railroads.
This structure doesn't cross under the Ozarks, but is very close to them. Just south of the Missouri River, the Ozarks dominate the landscape.
The interior of the tunnel is line with a combination of brick, stone and the natural rock bluff. The east portal is uncovered and is the natural rock, while the west portal is covered in stone.
The author has ranked the bridge as locally significant, because it is a rather short structure; despite it being a unique structure on the Katy Trail.
The photo above is looking east into the tunnel.