CHELYABINSK, RUSSIA—Three years ago, researchers discovered a 900-foot-long stone structure in the shape of a moose high in the Ural Mountains. Now further archaeological work at the massive geoglyph has uncovered clues to its construction and allowed researchers to date it to between 4000 and 3000 B.C. Some 155 stone tools have been found near the geoglyph, most of which were used for digging or breaking stones. "Judging by the different sizes of the tools—from 17cm-long and weighing about three kilograms to some being just two centimeters—we can assume they were used by both adults and children," Chelyabinsk History and Archaeology Institute archaeologist Stanislav Grigoryev told the Siberian Times. "We can also assume it means that everyone participated in creating the moose." It appears the Neolithic people who created the geoglyph dug 30-foot-wide trenches and then filled them in with stones. Grigoryev says the style of the moose seems to resemble petroglyphs found in Finland. To read about medieval ruins found at the center of a Siberian Lake, see "Fortress of Solitude."