The Petralona cave (Greek: Σπήλαιο Πετραλώνων) also Cave of the Red Stones (Greek: Σπήλαιο " Κόκκινες Πέτρες "), a Karst formation – is located at 300 m (984 ft) above sea-level on the western foot of Mount Katsika, about 1 km (0.62 mi) east of the eponymous village, about 35 km (22 mi) south-east of Thessaloniki city on the Chalkidiki peninsula, Greece. The site came to public attention when in 1960 a fossilized hominid skull was found. The cave had been discovered accidentally only a year earlier (1959) after erosion had left clefts in the rock. "Bejeweled" with impressive stalactite and stalagmite formations and holding an abundance of fossils, the cave soon attracted geologists and paleontologists. After decades of excavations the cave is open to the public and scientific work is documented and presented in an adjacent archaeological museum.[1]

The cave's most prominent fossil specimen, since known among paleoanthropologists as the "Petralona Skull", was named Archanthropus europaeus petraloniensis by Aris Poulianos, former head of the Anthropological Association of Greece. He considers it the oldest European hominid ever found, and assessed it to be 800,000 years old. Yet "there was the constant problem that the skull was an isolated find" as other scientists strongly disagree[2] and the find has been a continuing cause of controversy since. The Anthropological Association's conclusions and results are in direct conflict with accepted speciation models of the genus Homo and the chronology of the Out of Africa theory.[3]

Several times excavations on the site were delayed and/or had to be discontinued, first in 1967 and the following years in relation to the Greek coup d'état; again in 1983, according to Nickos A. Poulianos the Ministry of Culture giving no reason why it ceased to re-issue the excavation concession until "in 1997 the Anthropological Association of Greece, after 15 years of trials, was justified by the Supreme Court and was ordered the continuation of its works in the cave."[4] Dr. Aris Poulianos, President of the Anthropological Association of Greece, has repeatedly accused the Greek government of conspiring to suppress his discoveries, as in 2012 excavation rights were revoked again.[5]

The skull of the Archanthropus was according to Dr Aris Poulianos, head of the excavation team since 1965, found by another villager, Christos Sariannidis, in 1960, hanging on the wall about 30 cm (12 in) above ground, where it was held by sinter.[citation needed] Aris N. Poulianos states that "early estimates at the time placed the age of the hominid remains to around 70,000 years".[9] The Petralona skull, its lower jaw missing and completely "encrusted by brown calcite soon after the death of the individual" was estimated to be about 700,000 years old by Poulianos.[10] He announced that "the date was based on analyses of the cave's stratigraphy and the accumulated sediments".[11]

In 1981, the age of the Petralona skull deduced by Poulianos was investigated and the protocol published in the journal Nature. The scientists involved used electron spin resonance measurements of the calcite encrustation and of bone fragments, and dated the age of the skull to between 160,000 and 240,000 years.[12] However, Poulianos states that his excavations in the cave since 1968 provide evidence of human occupation from the Pleistocene era.[9] The Petralona hominid, specifically, was located in a stratigraphic layer containing the largest amount of tools and traces of habitation. Poulianos claims that the overall layer is about 670,000 years old, based on electron spin resonance measurements.[9][13] Other researchers point out, that contextual animal fossils "found with it are known elsewhere from approximately 350,000 years ago".[14][15] In 1987 researchers announced that the cranium cannot be older than 620,000 years, based on palaeo-magnetic and mineral magnetic studies of the cave's sediments

“Petralona cave.” Wikipedia, Wikimedia Foundation, 5 Feb. 2018, en.wikipedia.org/wiki/Petralona_cave.