Not far from the holed stone, the researchers found several intact burials known as grotticella tombs. Excavated in the rock, these chamber tombs were the main form of burial for the Castelluccio culture that fluorished in the Sicilian early Bronze Age.
Interestingly, on the east of the calendar rock, La Spina and colleagues found what appears to be a menhir, or upright stone. The 16.4-foot-tall stone lay on the ground, but the presence of a pit near its base suggests the megalith was originally standing upright.
"It stood at a distance of 26 feet, right in front of the rock's hole," La Spina said.
The geological composition of the calendar rock and the menhir are different, indicating the monolite was cut and brought to the site from elsewhere.
"This obviously reinforces the sacrality of the site," La Spina said.
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At least two other holed stones have been found in Sicily in the past.
"The newly found calendar rock appears to have been made by the same hand that carved the other two rocks," archeo-astronomy expert Alberto Scuderi, regional director of Italian Archaeologist Groups, told Seeker.
Scuderi discovered the two holed stones near Palermo.
"One lined up with the rising sun at the winter solstice, the other produced the same effect with the raising sun at the summer solstice," Scuderi said. "For this reason, I believe that another holed calendar stone, marking the summer solstice, may be found near Gela."
According to Giulio Magli, professor of archaeo-astronomy at Milan's Polytechnic University, the finding is very interesting, especially when associated to two holed stones found in the past.
"More research and scientific measurements must be taken," Magli said. "We should not consider the holed stones as a precise calendars or an instruments to observe the sun's cycle, but rather monuments that provided information on the solstices for practical and agricultural purposes."
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