For more than 200 years, the Jordanian city of Petra has been a sought-after destination for archeologists because of its ancient temples, intricate mosaics, and timeworn tombs.

But a Bangor, Maine, native has continued to make discoveries in the ancient Middle Eastern city, including a monument that archeologists had long walked over.

Starting about 3½ years ago, Sarah Parcak and other researchers looked at satellite images of Petra in the hope of finding significant landmarks. When the Maine native noticed an odd rectangular outline popping out of the earth less than a mile south of the city center, she was skeptical.

“I actually dismissed the find as being natural at first,’’ said Parcak, a researcher at the University of Alabama. “The edges of one of the sides matched up with natural ridges.’’

Then a colleague used a drone to take a high-resolution photo of the site, and they found the outline of an undiscovered man-made monument.

“He found the foundations of a structure,’’ Parcak said. “It was quite a large structure.’’

The monument consists of a platform that sits on top of a slightly larger one. The smaller platform had been paved with layered stones, according to a research paper about the discovery. The east side of the smaller platform was lined with columns that had bordered a stairway.

A small building was situated on top of the platform, Parcak’s team found. It opened to the east, away from the city.

The findings were published in a bulletin for The American Schools of Oriental Research, which is based at Boston University, and described Wednesday in a National Geographic article.

The site has not yet been excavated, so Parcak does not know how the monument was used.

“That’s typically something that could take a while,’’ she said. “I wish we knew, but this is also part of the fun of archeology.’’

The monument is not particularly easy to see, which can explain why no archeologist came across it before, Parcak said.

“If you know what to look for, you can actually see these courses of stone that show you that something’s there,’’ she said. “If you didn’t know that something’s there, you’d walk right over it.’’

This discovery is a reason for researchers to use more aerial technology, such as drones and satellite imagery, to uncover ancient sites, Parcak said.

“Even at very large and well-known world heritage sights, we’ve taken a lot for granted in terms of what’s there,’’ she said. “It’s important to use these new technologies to really allow us to look at them with a fresh pair of eyes.’’

J.D. Capelouto can be reached at jd.capelouto@globe.com. Follow him on Twitter @jdcapelouto.