This small stone arch bridge crosses a drainage ditch at the end of Pine Street in Iowa City.
Originally constructed at an unknown date, likely approximately 1880; the bridge was later expanded in 1901 with a concrete slab span to accommodate a second track.
As a result, the south face of the arch is currently not visible. This significantly detracts from the overall significance of the bridge.
While the date is uncertain for the stone arch portion of the structure, the author is working to find when it was built. It is possible that it could date as far back as the 1860s, or be as new as the 1890s.
Overall, the bridge remains in fair condition. Some pieces of stone are beginning to show signs of serious defects. Lining this structure with a piece of galvanized culvert would be the best way to preserve the bridge.
As for the name, the author looked into how the structure got the name "Dead Man's Cave". Citizens in Iowa City and on Facebook groups were not sure of the origin of the name, but also referred to this bridge as the Diamond Cave.
The author has ranked this bridge as being moderately significant, due to the possible extremely historic nature of this bridge.
The photo above is an overview. The bridge can be accessed from the end of Pine Street.