An Austrian farmer looking for his lost cat stumbled upon a hole that he thinks might contain the greatest UFO find of all time.

Franz Knoglinger, 47, found the 25-foot-deep, perfectly round hole in northwestern Austrian field while searching for his misplaced kitty Sunday night. He pulled out every investigative trick in the book to learn what was at the bottom.

Throw a rock down the hole? Check.

"I was looking for our family cat Murlimann when I noticed the hole -- I didn't know how deep it was then so I dropped the stone down there, and heard a metallic clunk," he told the Austrian Times.

Big ol' magnet? Check.

"I managed to get a big magnet which I dangled down there and it clearly fastened onto something at the bottom –- so there is something large and metallic about down there," he said. "It also sounds as if there is a hollow space around about whatever the metal object is. It sounds as if there is a room underneath."

He even called a local plumber, who lowered a camera down the pit on a rope -- but the camera failed just as it reached the object. Knoglinger said that the interference may have been caused by "some sort of electrical field."

Regardless, the speculations are already flying -- more than 500 people visited the site within the first day, the Salzburger Nachrichten reported (via Google Translate). Archaeologists told the paper that the hole could have been formed when wooden timber from an underground burial chamber rotted away.

But that doesn't explain the metallic object, which locals think could be a malfunctioned bomb from the war, the "Doorway to Hell" -- as one resident pointed out with a sandwich board -- or even a buried spacecraft, Knoglinger told the Austrian Times.

Geologists are expected to visit the site and perform tests before a possible excavation, the paper reported.

Meanwhile, Knoglinger found his cat.

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