Carnac is arguably Europe’s most visually remarkable megalithic sites. It is situated near the town of the same name in Brittany. Many will have seen images of the rows of standing stones there, often unaware that there are four main sets of them close to Carnac as well as cromlechs and solitary menhirs, including the largest, Le Grand Menhir Brisé, now broken, but originally 70 ft long and weighing around 300 tons. In their 1978 book [1771.180], Alexander Thom and his son, Archie, in the conclusion to their book, in spite of their extensive studies of the stone rows, agreed that “we do not know what these were for” and although various theories have been proposed since, we still don’t.
Jean Markale presumed that there was a connection between Atlantis and the megalithic standing stones of Carnac in Brittany. Rather than solve these two mysteries, his book, Carnac et L’enigme de L’atlantide (Carnac and the Enigma of Atlantis)  would seem to deepen them.
Helmut Tributsch suggested that the island of Gavrinis near Carnac in Brittany had been the capital of this Atlantean civilisation(a). He dated the destruction of Atlantis to 2200 BC, a date also favoured by Anton Mifsud.
Hans-Pény Hirmenech expressed the wild idea that the rows of standing stones at Carnac marked the tombs of Atlantean soldiers who fought in the Trojan War! Wikipedia notes that “A Christian myth associated with the stones held that they were pagan soldiers in pursuit of Pope Cornelius when he turned them to stone.”(a)
Hank Harrison supports the idea of a megalithic Atlantis with its centre of power, probably located in the Morbihan area of Brittany.
Based on the picture the data present, Schulz Paulsson believes that the megaliths were first constructed by dwellers of northwest France during the second half of the fifth millennium BC.”(b) Mike Parker Pearson, Stonehenge’s leading authority, has endorsed this idea of a French origin for megalith building(c).
The Mzora Stone Circle is a huge megalithic monument in Morocco and is in fact the largest stone ellipse in the world. Mzora and the Egyptian Nabta Playa site are claimed to have used the same construction methods that Alexander Thom has shown to have been used by the British megalith builders. A recent article by Sarah P. Young claims that “The circle is constructed using a Pythagorean right angled triangle with the ratios 12, 35, 37 and this is the same method used by 30 megalithic stone circles in Britain alone. Other similarities in construction and proportions exist such as the use of the so called ‘megalithic yard – a unit of measurement which seems to have been universally employed across Europe – and evidently even further afield” (g).
Although no formal claim has been made for any connection with Atlantis, the supporters of the idea that the megalith builders were Atlanteans see the complexity of the Mzora site as further justification for their opinion. A July 2018 paper(f) links the ancient Berbers with Mzora and as the Berbers occupied territory described by Plato as Atlantean (Timaeus 25a-b & Critias 114c), Mzora may also be legitimately described as Atlantean.
James Mavor, better known for his research at Santorini, surveyed the Mzora site in the 1970s. Bob Quinn visited the site in 1982 and was struck by its similarity with Newgrange! Robert Temple discusses the site at length in his Egyptian Dawn.>According to Hugh Newman in a paper on the global ubiquity of stone circles(h), he refers to Mavor’s work and notes that Mzora “appears to have been constructed either by the same culture that erected the megalithic sites in France, Britain and Ireland or by one that was intimately connected with them.”<
John E. Palmer visited and surveyed the site in 1978 and subsequently wrote an article for Kadath magazine, unfortunately in French only. He reported that extensive damage was done to the site by ‘archaeologist’ César Luis de Montalban with excavations in 1935-6(d) and that many of the stones have been broken by ignorant Islamic extremists.
In 2011, Graham Salisbury gave coordinates for the site and offers a history of Mzora in a longer article(b).