Black Diamond Historical Cemetery is located in Black Diamond, Washington. Once known for its coal mining, the cemetery was founded in 1884. It sits on Cemetery Hill Road, hidden by a row of trees. The only indication of its existence is a wooden sign erected by local Scouts.
The earliest gravestone dates back to 1880 and now contains over 1100 graves. the tombstones show cultural diversity and tragedy that existed in town when coal mining was at its peak. At least half a dozen graves mark belong to those of mine workers who died in explosions in 1902, 1910 and 1915. Graves mark residents who came from countries such as Italy, Australia, Russia and Germany. A Civil War veteran was laid to rest in Black Diamond as well as children who died in the early 1900s due to epidemics of small pox and influenza.
Being a cemetery, it's not too unusual the property has a haunted title attached to it. Paranormal reports have been quite consistent even though plausible explanations could be determined for all and there are no records when the activity began. On foggy nights, looking in to the cemetery, you can see swinging lights supposedly belonging to a deceased coal miner (or possibly the product of a natural gas phenomena). Some have heard whistling in the wind (it's an open area. sounds could come from anywhere especially carried on the wind). There are also reports of a white horse seen trotting around headstones (Black Diamond is a rural area. An actual horse may have gotten loose. One witness and the story is added to its haunted persona).
However, several local paranormal groups have investigated Black Diamond Cemetery. One group captured a mist on several photographs (whether it was natural or supernatural, I can not say). From what I can tell Puget Sound Ghost Hunters is the only one with a rather detail report of their investigation. Their visit ended with virtually no physical evidence but personal experiences including odd aromas, feeling of being watched and a light anomaly. You can view their detail report here. Is Black Diamond Cemetery haunted? Although I personally feel cemeteries should be off limits, only future investigations can confirm or deny it.