A mysterious metal monolith that appeared four days ago in Romania, similar to one that appeared two weeks ago in the U.S., has vanished.

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A metal pillar found about two weeks ago in the Utah desert generated international interest and intrigue. After internet sleuths determined its location, visitors flocked to see it. A day later it disappeared. Who put it there, when and why are still unclear.

>> Mysterious metal pillar found in Utah desert

The Romanian structure is not so enigmatic.

>> Mystery of the metal monolith found in Utah desert partially solved

It appeared Friday as a prank by a local metal-worker. The 9-foot tall pieces of sheet metal had intentional swirls and poorly welded joints. It was removed Tuesday, but the question remains, by who?

>> Mystery monolith in Utah disappears

“An unidentified person, apparently a bad local welder, made it,” Robert Iosub, a reporter for the Ziar Piatra Neamt newspaper who visited the pillar, told Reuters. “Now all that remains is just a small hole covered by rocky soil.”

The structure was placed on Batca Doamnei Hill, a protected archaeological area where a Dacian castle once was. Georgiana Mozu, a Piatra Neamt police spokesperson, said officers are investigating the illegally installed pillar.

Cox Media Group