There's gold in them there hills. Or, at least there used to be. Explorers recently found a way into the now abandoned Union gold and silver mine to see what remains hundreds of feet under the Earth.

So much history lies in the Black Hills of South Dakota within these rocks. The YouTube channel Mines of the West shared this backstory about what the Union Mine used to be:

The Union Mine was once one of the largest underground mine complexes in the state. The complex was made up of dozens of individual mines that eventually joined together. The mines were developed by dozens of shafts...and open stopes. What is so impressive about this site is that 90% of the development was completed before 1900. By the turn of the century, the mine had reached a depth of 1,300 ft. and nearly 25 miles of workings had been driven.

The estimate they're the first people in decades to see inside the Union Mine. By the looks of what they found, they were right. The exploration came in 3 parts they've shared.

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Western Mining History has some more facts about the old Union Mine. They show that it's still owned by Golden Reward Consolidated Gold Mining And Milling Co., but it hasn't been active for decades.

These guys began their investigation in a stoke chamber that was in severe disrepair. To say that this isn't the type of journey you want to undertake without some type of professional guidance and approval is an understatement. The dangers in an abandoned facility like this are legion. Fortunately, they did it safely so the rest of us can see what lies beneath in what used to be a vital source of silver and gold in the region.

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