Marengo Cave is an enormous, beautiful natural cave in Indiana. It's easily traversable for tourists, isn't particularly muddy or wet, and is absolutely beautiful.

A group of children discovered the cave in 1883, and the townsfolk—immediately recognizing a potential tourist attraction—quickly declared it a protected site. A few years ago, Marengo Cave was declared a US National Landmark.

It's not the only cave in Marengo, Indiana, though.

The Marengo Warehouse is an old underground limestone quarry located just a few miles away from Marengo Cave. Opened in the 1800s, it contains almost four million square feet of storage space (more than 100 acres), about a quarter of which is in use. The owners converted it from a mine to a storage warehouse in response to competition from much larger limestone quarries.

All sorts of rumors swirl around the warehouse. For example, the Center for Disease Control supposedly stored supplies there for a long time, but the only actual government property inside are some 10 million MREs. The other contents of the warehouse include 400,000 tires and some 23 million pounds of frozen fruit, most of which are intended for use in yogurt.

The Marengo Warehouse is nowhere near unique. All around the world, we’ve converted limestone mines into storage spaces and business parks. This depends on how we mine the limestone. Since the 1950s, miners have worked carefully to ensure that the leftover space is actually useful, carefully removing 12-foot thick chunks of stone in grid-shaped patterns. When mining is completed, very little construction is needed to ready a cave for other purposes.

The underground limestone quarries are extremely stable. Limestone is made of compressed, ancient, tiny seashells. It's three times stronger than concrete, and has been used in construction for more than three thousand years.

Me…in my man cave.

Of course, there are certain concerns with use of the quarries. Ventilation is a much greater concern than in other mines, so electric forklifts are generally required instead of those powered by propane powered. And, while the older quarries are generally extremely stable, the geological strata above and below the facility must be monitored, to watch for shifting or cracking rock layers.

Now, I’m way too hopeful a man to get all bothered by doomsday scenarios, but if you really want to start preparing for all possibilities, those limestone caves might one day save the human race. I’ll stick to my man cave…when Maggie lets me, of course.
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Quotable

Oh, Yard Ramp Guy, just me here, staying on topic with my quotations:

“The cave you fear to enter holds the treasure you seek.”

— Joseph Campbell

I write a lot about roads on this blog. The Yard Ramp Guy must think I'm a bit obsessed (though he’d probably phrase it differently).

The study of roads is the study of history. Countless historical events, from the outcomes of wars to international trade, and from religious expansion to the maintenance of nations: they all rely on roads.

Incan roads—not the most extensive network of ancient roads but one of the most technologically impressive—were earthquake-proof with incredibly durable suspension bridges. Roman roads have been receiving acclaim for millennia now, and many are still in use.

Which brings us to ancient Chinese roads.

Under the Qin Dynasty (circa 220 BC), Chinese road networks were considerably more extensive than their Roman contemporaries. One, the Ancient Road of Mules and Horses, was created in 214 BC by an advancing army of the Qin. The Emperor marched a half-million strong army in a straight line on one of his wars of conquest, crushing the earth in its path. They later covered the road in slate, and it remained in use for 2,000 years afterward without changing routes.

Walking up a golden ramp. Kind of.

Road maintenance was key in holding onto territory in China. Later dynasties, like the Han, went to great pains to maintain this and other roads, building hostels and post offices along their lengths. Another Qin road was immensely long, built to service border forts along a huge wall that predated the Great Wall.

My favorite ancient road of all, though, is the Stone Cattle Road. One of the ancestors of the First Qin Emperor wanted to conquer the nearby Shu kingdom to the south, over the Qinling Mountains. He had his sculptors and artisans carve five life-sized stone cows and decorate their tails and hindquarters with gold.

When the king of Shu received news of them, he asked the Qin king to send him a herd. The Qin king claimed that he would need a gallery road (built of wooden planks imbedded in the sides of cliffs) across the mountains to move the cows. The Shu king not only permitted it; he also helped fund the construction.

Yes, we know how this story develops: The first thing the Qin king brought over wasn't a herd of gold-depositing cattle. He brought an army.

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Quotable

Oh, Yard Ramp Guy, the road to great quotations is paved with good intentions:

“Roads are long: make them short with a good company!”

— Mehmet Murat ildan

We’ve heard of the Stone Age, the Bronze Age, and the Iron Age. And yet, we aren't commonly taught why those ages occurred in that order. Which is just too bad, since it's pretty darn interesting.

The Stone Age has a simple explanation. Stone is easier to work than metal, and more common. We figured out how to use it first.

Ancient humans actually did master use of some metal during this time period— namely meteoric iron, a natural alloy of nickel and iron present in iron meteorites. We sometimes heated it but more often shaped it, by cold hammering, into tools and arrowheads; the stuff was quite difficult to work.

The ancient Inuit inhabitants of Greenland, though, used iron much more extensively than other Stone Age people. Greenland has the world's only major deposit of telluric iron, also called native iron, which is iron that occurs in its pure metal state.

Looking for the right tool to advance our evolution

Native copper, however, is found worldwide (as are native gold, silver, and platinum, all of which are of limited use for tools.) The hardest and strongest common native metal on Earth, copper proved one of the most useful.

Eventually we learned to smelt metals from ore and, around 2500 BC, learned to alloy the two together to make bronze, kicking off The Bronze Age. Tin was somewhat rare outside the British Isles, parts of China, and South Africa, so it actually ended up commanding prices higher than gold in many regions. We frequently used zinc, more common than tin, to produce brass.

Iron smelting first occurred circa 1800 BC but didn't become common until 1200 BC. Eventually, of course, iron became the metal of choice for civilization—it's just much stronger than most of the other options.

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Quotable

Oh, Yard Ramp Guy, and I quote:

“Stone Age. Bronze Age. Iron Age. We define entire epics of humanity by the technology they use.”

— Reed Hastings

All traffic isn't created equal.

For example, you've likely noticed that the morning rush hour often has greater traffic coming into the city from the suburbs and that the evening rush hour traffic clogs up the outbound lanes.

So, we tend to have traffic moving much more slowly in one direction than the other.

Accidents and our tendency to rubberneck them also cause the traffic to bunch in one direction. (Yes, we can keep listing these reasons for a while.) Unfortunately, building new lanes for our roadways can be prohibitively expensive, and it often isn't even possible, especially where bridges are concerned.

There is a fascinating solution, though:

Road zippers are heavy vehicles that have the ability to move concrete lane dividers across a lane, widening the road for one direction of traffic, narrowing it for the other. This requires a special type of moveable barrier, with shorter segments linked together by flexible steel connectors.

The road zipper, plus new barriers, are far, far cheaper than an entirely new lane. They actually pick up the segment lines using a little conveyor system, essentially acting on the same principles as a screw or a ramp (though Jeff Mann, The Yard Ramp Guy, might think I'm stretching that definition a bit).

Road zippers can move the lane at up to a top speed of 10 mph, depending on traffic, and is much safer than trying to manage traffic with cones and lights. They're especially useful on bridges. Crews on the Golden Gate Bridge have been employing a road zipper since 2010 to manage rush hour traffic, to great effect.

Any road crew that's worked on a bridge isn't going to have particularly fond memories of dealing with bridge traffic, and the road zipper provides an effective solution. We can also use this method to speed up bridge re-decking projects, moving the barrier to protect the work zone.

Transportation authorities utilize road zippers all around the world, and they're especially popular in the United States and Australia. Many cities use them on a permanent basis, while others lease them temporarily during construction work.

Even if they weren't so useful logistically, I'd still like them: they're just plain cool.

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Quotable

Oh, Yard Ramp Guy, while I like your sports quotes (go, team), I tend to stay on topic:

“If you don’t know where you are going, any road will get you there.”

— Lewis Carroll

Don Justo at age 85

Some people’s work ethics are entirely too formidable. I'm by no means a lazy man, but sometimes even I like to relax and spend an entire day on the lake with a fishing pole.

Not Justo Gallego Martínez. Known also as Don Justo, he is a former monk, living in Spain, and he’s been building his own cathedral for decades.

After eight years of living in a Trappist monastery, he left the order due to tuberculosis. And he promised himself that he would build a shrine if he recovered. Don Justo started work on the cathedral in 1961.

Martínez's work begins each morning at 6 AM and lasts for about ten hours a day. He takes off only on Sundays. He has missed but a handful of days during the decades of the cathedral’s construction, and he’s done the vast majority of the work completely alone, though he does have a helper these days.

When he started, there was no plan. He just leveled the ground and started building. To this day, he regularly changes the design, according to inspiration or whim. The cathedral doesn't have any planning permissions from the city of Mejorada del Campo, nor does it have the blessing of any part of the Catholic Church.

Despite the lack of city permissions, Don Justo hasn't had to deal with any real trouble from the city. Most residents are quite proud of it, though a small number consider it an eyesore.

Most of the materials he uses for construction are recycled. Local construction companies and a nearby brick factory frequently donate excess material to the project. Frequently, he also folds everyday objects into the design. For example, he molded his columns with old oil drums.

I've thrown up a few sheds in my life, but a whole cathedral? I don't have a fraction of the ambition to handle that. And then there’s Don Justo, who doesn't even use a crane. And he's 90 now. Not for me.

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Quotable

That other Yard Ramp Guy keeps on quoting, and, I must say, his choices are pretty good, if a bit too tilted toward sports. Oh, well. As Michael Jordan said, “Just play. Have fun. Enjoy the game.” So, en garde, Yard Ramp Guy:

“If opportunity doesn’t knock, build a door.”

— Milton Berle