An abandoned masonry tunnel exists deep under Walnut Hills in the vicinity of the abandoned CL&N RR right-of-way, near present-day I-71. The north portal was located 1,000ft. south of Blair Ave. and the south portal 700ft. south of Eden Park Drive. It was built by the Cincinnati & Dayton Railroad and was to have carried a pair of six foot broad gague at a .75% grade from south to north passing as much as 200ft. beneath the hills above. Approximately 3,500 of a planned 9,000ft. were dug before construction was abandoned in 1855. The completed southern portion apparently became a gang hang out as well as a place where runaway slaves were hidden. It was sometimes rumored that this is where the term "Underground Railroad" originated, although that claim appears to be false.

In 1927 the tunnel was investigated for use in the incomplete Rapid Transit Loop  as a northeastern connection and completion of the loop. It was determined that the only practical location for a station was at Kenton and McMillan, at which point the tunnel is its maximum 200ft. below the surface. A station would not only have been extremely expensive to construct, but would have also involved a time consuming elevator ride to the platforms.  Additionally, the platforms would have sloped along with the alignment of the tunnel.  This, plus the tunnel being only 30% complete, eliminated it from consideration. It was noted at the time that the tunnel was "of solid masonry construction", and in good condition, with the exception of a cave-in at the southern portal.

A recent search for signs of the tunnel revealed no signs of its presence whatsoever. The south portal was located in the approximate location of an elevated section of I-71 northbound, a few hundred feet south of the Eden Park Dr./Dorchester exit, and was covered by expressway construction. The north portal was still visible according to a 1950's account, but it appears to have been covered as well. The Deer Creek Tunnel has been completely forgotten by the general public, and is known by few other than railroad enthusiasts.

In late November 2007, excavation for a parking garage at the corner of Eden Park Drive and Florence Ave. unknowingly pierced the roof of the tunnel. A sink hole developed and on the morning of December 5 workers arrived in the morning to find a track hoe parked over the tunnel had fallen partly into it. The vehicle caught on piles that had recently been dug and so did not fall completely into the tunnel, in which case it would have disappered completely from sight.

[Dec 5, 2007 Jake Mecklenborg]

This satellite image shows the intended route of the tunnel.  Downtown Cincinnati is located at the bottom left and I-71 is clearly visible along the path of the tunnel.
 

Recent photo of the vicinity of the southern portal, looking north.
 

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