LOS ANGELES (CBS) — At 340 tons, it’s one of the largest boulders to be moved since ancient times.

And starting Tuesday, a granite megalith is expected to begin an 11-night journey from Riverside County to the Los Angeles County Museum of Art (LACMA).

The boulder will make its way through four counties and 22 cities, the museum said on its website.

Once it arrives, it will be part of Michael Heizer’s “Levitated Mass” exhibit.

According to the museum, Heizer conceived of the artwork in 1968 but did not discover an appropriate boulder until decades later.

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