12 rare photos inside an unusual, beautiful mine that's hidden 2,000 feet below Lake Erie

Morton Salt Mine runs about three miles under Lake Erie.

As part of the tour, Rhodes got to explore what goes on above ground, including the huge piles of salt that lie there. Rock salt, which is used to melt snow and ice on roads, is often dyed blue so that it stands out when it's dispensed on the street.

Source: Chromatech Colors

Driving by the mine above ground, you would never know that it's there. "Manufacturing equipment and detritus is pretty common in Cleveland, so I don't think people think too much into this," Rhodes said. "I'm not sure that people connect the large piles of salt to the massive mining operation happening 2,000 feet below the lake."

Workers can enter the mine by taking a four-minute elevator ride.

Much of the salt is moved from underground to above after it is broken up. Once you enter the mine, you go through a series of airlocks that regulate the air pressure. Fresh air from the surface is pumped down the mine shaft to supply oxygen to the miners.

Workers are required to wear safety glasses, an emergency air pack that holds an hour's worth of oxygen, and protective head gear with headlights to help see around the dark area.

Inside the mine it's completely "pitch black", Rhodes said. Luckily, his powerful photo gear was able to bring the area to life. He used the Canon 1DX camera and two Profoto AcuteB 600s, an on-location lighting setup, to capture the interior.

The first operation for mining rock salt is undercutting, a process by which large machines cut a space 10 or more feet deep into a solid salt wall.

Source: Morton Salt

Then, small holes are drilled into the salt wall, and explosives are put into the holes. At the end of the day, explosives go off electrically.

Source: Morton Salt

From that, several hundred to several thousand tons of rock salt are blasted. Ohio ranks fourth in salt production nationally and produces five million tons of rock salt a year. "Personally, I thought the mine was beautiful," Rhodes said.

Source: Ohio History

Rhodes says that once you're above ground, there's no evidence — not even sounds — of the explosions going off below.

The mine is extremely large," Rhodes said. "It is a bit eerie because other than my tour guide and assistant, there were not too many people we came across.