A boulder-sized "rune stone" that went missing from the coast of Rhode Island has been found and returned due to the help of an anonymous tipster.

The stone is "a Rhode Island formation meta-sandstone that is 7 feet long, 5 feet high and 2.5 feet high [2.1 X 1.5 X 0.8 meters] and is inscribed with two rows of symbols, which some have indicated resemble ancient Runic characters," according to a news release from the state's Attorney General's office and the Department of Environmental Management. It went missing last summer, but is now back in the hands of the state, WPRO reported. How or why somebody managed to move the enormous rock is unknown.

The Quidnessett Rock, also known as the Narragansett Rune Stone, has attracted attention since the 1980s for its strange inscriptions, which resemble ancient Norse runes, according to the Boston Globe (before the 1980s it may have been buried.) Although some claim the runes are evidence of a visit by Vikings, this hasn't been verified.

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