A Texas Sized Mystery: Solved

On a flight from New York City's LaGuardia to Washington's Reagan Airport I captured some photos of this curious sight:

Given its size and proximity to a main road, I figured I'd quickly identify it. But alas, trawling through Google Maps, chatting with ChatGPT and searching along FlightAware flight paths turned up nothing.

I finally gave up, and simply pronounced: I'd have to solve the mystery on our next flight from LGA to DCA.

My Dad wasn't having it. He took one look at the photo and explained, "you're looking for a quarry. It should be easy to find."

And a few days later he texted me with the answer!

I'd taken aerial photos of the Martin Marietta - Texas Quarry:

At first, I was like, "that's close Dad, but that can't be it. My photo includes a sort of racetrack type structure in the foreground, and I don't see that in the image."

To which he replied, and I'm paraphrasing here: zoom out.

Whoa! The "racetrack" was in fact the Maryland State Fair Grounds and was an exact match for the feature I was looking at.

He'd done it! He'd solved the mystery! Thanks, Dad!

When I asked him how he did it, he explained that he asked Gemini for a "list of quarries that can be seen from a plane on a flight from DCA to LGA" and then ran them down in Google Maps. Inspired by his effort, I tried again with Gemini.

I tried the prompt: "I took this photo on a flight from LGA to DCA. It appears to be a quarry. Any idea which quarry it is?" The first time I asked, I got a false positive. Trying again with the exact same image and prompt found it!

I can't believe the answer was there all along, I just had to know how to ask. I suppose this is the quintessential challenge when working with AI: knowing how to ask.

With the quarry identified, I was curious: (a) where did it get its name from, and (b) is it significant?

The name, Martin Marietta - Texas Quarry is easy to unpack. The quarry is currently owned by the company Martin Marietta. The "Texas Quarry" part comes from the fact that it's located in a Maryland village that used to be known as Texas. This location name has been in use since at least 1847.

As for (b), the quarry does appear to be significant. From what I can tell, marble from this site was used in the Washington Monument as well as other local sites. Here's how the USGS describes the marble that was used in the construction of the Washington Monument (emphasis is mine):

Three different kinds of marble were used in the construction of the Washington Monument, which was delayed by several problems. ... The first 152 feet of the monument, built between 1848 and 1854, is faced with marble from Texas, Md. Work stopped when funds ran out.

That sounds like my quarry, or at least one in the vicinity.

Another hint to the significance of this area, is this article published in 1874. It provides extensive details about the "Beaverdam Quarry", explaining that it was also known as the Cockeysville Quarries. The article proudly notes that "the National Capitol was built of marble from this quarry." It specifically calls out the "post-office building of Washington was also constructed of the same material."

Not only is the Texas Quarry located in Cockeysville, MD, but Beaverdam Road runs adjacent to the property. So while I can't say for sure the article is talking about the same quarry I photographed, it certainly seems to be in the same neighborhood.

What a gratifying mystery to solve! Thanks, Dad!