The ghostly salt city beneath Detroit

The ghostly salt city beneath Detroit hardly seems real:

Like a Jules Verne fantasy, a ghostly city with its own network of four lane highways lies deep beneath the industrial heart of Detroit, its crystalline walls glittering and gleaming in the flickering light. It is a world of no night or day.

It is a world of salt.

This gigantic salt mine, 1,200 feet beneath the surface, spreads out over more than 1,400 acres with 50 miles of roads. It lies underneath Dearborn's Rouge complex , much of Melvindale and the north end of Allen Park. The mine shaft opening is in Detroit.

Some (pre)history:

In Michigan, a huge sea covering the region evaporated more than 400 million years ago, forming salt deposits which were gradually buried by glacial activity. This salt bed spreads over 170,000 square miles under Michigan, Ontario, Ohio, Pennsylvania, New York and West Virginia.

Some estimates suggest that there is enough salt in the Metro Detroit underground to last 70 million years.

Michigan's Indian tribes used salt springs long before the white man came. Salt Creek, 32 miles west of Saginaw, supplied Indians and forest animals with salt crystallized from brine springs.

In 1841, Douglas Houghton supervised the sinking of the state's first salt well in central Michigan, the beginning of a series of borings that led to the establishment of the Dow Chemical Company and the discovery of the central Michigan oil and gas fields.

Some of the operational details are crazy:

Mules, lowered by rope down the narrow shaft into the mine, were used in the early mining operations. Once down in the mines, they stayed there until they died.

Workers decended in a two-level elevator in which six men pressed face-to-face during the long ride down.

Getting equipment down into the massive cavern provided many problems. Pickup trucks, jeeps and large trucks had to be cut up or disassembled and lowered down the shaft piece by piece, to be reassembled in shop areas below. Large dump truck tires too big for the shaft had to be compressed and bound before they would fit down the opening.

In a 1925 Detroit News article, miner Joel Payton told about his salt mine job. "The only dirty part of this job is going down to work," Mr. Payton explained.

"I have to wear this old outfit because the big buckets that take us down get smudgy from the action of the sulphur water on the iron of the buckets.

"The mine itself is dry and clean as pure rock salt in a solid vein 35 feet thick is bound to be. The high vaulted rooms that we have hollowed out have sparkling white floors, walls and ceilings."

Payton continued, "One reason we don't have any rats in our Detroit mine is because the rats would have nothing to eat except the leavings of our lunch pails. And by the way, not only are there no rats or cockroaches or other living creature in our mine, but also no remains of living things from past ages. The salt vein is, of course, a dried up sea that once covered this section for hundreds of miles. You'd naturally suppose that some fish or vegetation would have been pickled or fossilized in the brine as it hardened. But I've never seen a single fossil or sea shell or any remains of that kind"

The Detroit mine used the room-and-pillar method of removing salt from the ground. In room-and-pillar mining, shafts are sunk into the ground, and miners break up the rock salt with drills after detonation engineers had blasted a section. Each blast brought down 800 to 900 tons of rock salt. The miners removed chucks of salt, creating huge rooms separated by pillars of salt. The room-and-pillar method requires that about half of the salt be left behind as pillars for support.

The tunnels, dark and cavernous seem eerie lit only by truck lights or the single bulbs along the sides.