Alfonso d’Ascanio is a Spanish legal expert with a long-standing interest in Plato’s Atlantis. He is the author of El naufrago del Julán , which is a novel that explores the history of the Canaries and the origins of its Guanche inhabitants. His grandfather published a book in 1922 which investigates the geology of the Canaries. His father, also Alfonso d’Ascanio, was also preparing to finish a book in the late 1950’s(a), which was intended to demonstrate that Atlantis had been situated in the Atlantic, where its remnants are now the Macaronesian groups of islands (Canaries, Azores, Madeira & Cape Verde). D’Ascanio snr also contributed to Egerton Sykes‘ Atlantis magazine.
(a) Atlantis, Vol.12, No.1, Nov/Dec 1958
William Richard Harris (1847-1923) was Irish by birth, but moved to Canada at an early age, where he became a Catholic priest eventually becoming Dean of St. Catharines Church in Toronto. His many interests included history and anthropology, which led to a compilation of some of his lectures being published as Prehistoric Man in America.
He believed in pre-Columbian contact with America by Europeans, citing the Italian historian Ludovico Antonio Muratori, who showed that Brazil wood was a taxable commodity at the Port of Modena as early as 1306!
In the final chapter he discusses the existence of Atlantis, quoting both classical and modern authors. He concludes with his belief that Atlantis was located in the Atlantic with the Canaries, Azores and Cape Verde as its remnants.
Geodesy is usually defined as the measurement and mapping of the Earth. As a science, it is traced back to Pythagoras (6th cent. BC), who was thought to be the first to propose the sphericity of the Earth. Later, Eratosthenes (276 BC– 195 BC) was one of the earliest to attempt to determine the dimensions of our Earth and succeeded with remarkable accuracy.
A controversial aspect of modern geodesy is the claim that many ancient sites were deliberately established at locations that had a specific geodetic relationship to each other and/or the dimensions of the Earth. For example(a) in ancient Egypt, from Giza to the Equator is 1/12th the circumference of the Earth, Amarna to the Equator is 1/13th, Luxor 1/14th and Philae 1/15th! Graham Hancock in his Heaven’s Mirror pointed to similar relationships around the globe suggesting a possible world grid. This idea of a world grid has a number of supporters but is often classified as a ‘fringe’ interest due to the attempt by some to link gridlines with UFOs and their use of the grid as a power source(w).
Possibly related features may be the ley lines identified by Alfred Watkins in Britain(c)(g), the Alesia alignments in France discovered by Xavier Guichard(b) and/or the Heilige Linien of Germany claimed by Wilhelm Teudt(aa).
Heinz Kaminski had claimed to have discovered a megalithic grid system that stretched from Stonehenge across Europe with an east-west and north-south orientation and referred to as the Stonehenge/Wormbach System(h).
Even more exotic is the ancient Raetiastone navigation system rediscovered by Gerhard Pirchl (1942-2013) and outlined in a book by  Thomas Walli(ae).
Ashley Cowie has published a paper(ac) related to Alesia and the work of Guichard and others, as well as his own investigations.
I should also point out that Marcel Mestdagh also identified a form of a road system, laid out in giant ovals with radials in France. At the centre of these ovals was the ancient city of Sens. Philip Coppens informs us [1275.184] that a further strange discovery by Mestdagh was that this ancient road network, centred on Sens, was mirrored by a similar network of roads in England centred on Nottingham!
‘The Way of Virachoca’ in the Andes which runs through Tiwanaku and is oriented exactly 45° west of true north and runs for over 1000 miles, has been studied by Maria Scholten d’Ebneth  in the 1970s and expanded on by a number of Spanish speaking commentators and is now the subject of an article by Dave Truman(x).
In 1973, three Russians, engineers Valery Makarov and Vyacheslav Morozov along with Nikolay Goncharov, an artist, published in Russian an article with the eye-catching title of Is the Earth a Giant Crystal? (y) This was probably the earliest presentation of an earth grid based on ancient historical sites. A brief history of the earth grid theories that emerged around this time is available online(z). There is now a Russian geodesy website with an English translation(ab).
David Hatcher Childress published his Anti-Gravity and the World Grid  in 1993, with the modest claim that he “proves that the earth is surrounded by an intricate electronic grid network offering free energy.” Obviously, Childress’ understanding of ‘proof’ is different to mine, as the only proof required is the production of some of this free energy, which he has not done.
Tom Brooks has entered the fray with a study of 1500 prehistoric sites and his conclusion that the inhabitants of ancient Britain had a designed a navigation system based on a grid of isosceles triangles(i). Brooks has gone a step further and speculatively claimed that the accuracy of this geometry-based system could only have been designed through “extraterrestrial intervention”(r). This concept is explored more fully in his latest book, Seeing Around Corners: Geometry in Stone Age Britain  and in a series of video clips(s). A more critical view of Brooks’ ideas is also available on the Internet(j).
Some years ago a former employee of a NASA sub-contractor, Maurice Chatelain claimed that within a 450-mile radius of the Aegean island of Delos that 13 mystical sites, when connected by straight lines formed a perfect Maltese Cross(u)!
Others such as Livio Stecchini(d) and Jim Alison(e) using geodetic calculations have identified São Tomé and Cape Verde respectively as the location of Atlantis. I must also include Hugo Kennes, a Belgian researcher with a passionate interest in global grids and sacred geometry(l). Kennes has also informed me of a new Facebook group(q) deal with all aspects of the subject, as well as another(v) that includes submerged cities and other features.
Anyone interested in pursuing a study of this subject might like to look over James Q. Jacobs’ archaeogeodesy website(f) as well as the BioGeometry website (m).
If you have pursued all the links so far, you can pamper yourself further with a paper(k) by William Becker and Beth Hagens(n). Another researcher in this field is Dan Shaw whose website(o) gives a good overview of the subject.
Jean-Pierre Lacroix added his weight to the debate with his 1998 paper entitled The Mapmakers from the Ice Age(t).
A global network of sacred sites was also put forward by Rand Flem-Ath & Colin Wilson in The Atlantis Blueprint . This book was intended as a sequel to When the Sky Fell , but generally wandered off into other areas after the first couple of chapters.
I am somewhat sceptical about certain aspects of geodesy, particularly some of the claims of a world grid. However, it does raise many questions that require further study and explanation. In this connection, I would recommend John Sase’s Curious Alignments  as a good starting point. He confirms the work of Guichard and also offers a range of his own discoveries in the Great Lakes region.
In February 2020, Frank Maglione Nicholson, Ken Phungrasamee & David Grimason, collectively known as The Nazca Group(ad), published The Nazca Great Circle Map Hypothesis. Their claim is that “The lines and geoglyphs carved into the Nazca plateau represent a map of the Earth. The map is a Great Circle Map: a gnomonic projection with the center of the Earth as its cartographic view point. Each line on the Nazca Plateau represents a great circle of navigation centered at the center of the Earth and encircling the entire planet. The majority of the lines on the Nazca Plateau radiate from five loci of origin called radial centers.” I found this rather esoteric proposition difficult to absorb.
>Arturo Villamarin has published many books  and papers(af)(ag) in which the geometry and astronomy of archaeological monuments; Göbekli Tepe, Stonehenge, Teotihuacán and Mohenjo Daro, among others, are discussed.<
(d) http://www.metrum.org/mapping/atlantis.htm (link broken Dec. 2020)
(r) https://www.prehistoric-geometry.co.uk/ [See (i)]
Jim Alison has written an extensive paper(a) on the highly controversial subject of a global aligment of ancient sites such as the Great Pyramid, Easter Island and Machu Picchu(b). At the end of the first page he concludes that the Cape Verde islands are possibly the remnants of Plato’s Atlantis, based on the geodetic fact that “Machu Picchu and the Great Pyramid are equally distant from the Cape Verde Islands. Easter Island and the Indus Valley are also equally distant from Cape Verde.” For similar reasons he thinks that the Bay of Bengal as well as near Ilha Martin Vaz, a location off the coast of Brazil, should also be considered as possible candidates.
Hermann Wirth (1885-1981) was a Dutch historian who became one of the co-founders of Himmler’s Ahnenerbe-SS. He was obsessed with Atlantis and sought to prove that it had existed in the North Atlantic where he believed that it had stretched from Iceland to the Azores. He thought that the only parts of Atlantis to remain above water after its submergence were Cape Verde and the Canary Islands. Wirth named this North Atlantic Atlantis, Thule after the ancient writer Pytheas. He also concluded that a pure monotheistic religion had originated in a common homeland, possibly Plato’s Atlantis(a).
The Nazis who came to believe that the Aryan race had originated on Thule adopted the idea. Wirth also translated the controversial Oera Linda Book, using it to support the party line on Germanic origins(b).
Edgar Dacqué (1878-1945) was a leading German Professor of Palaeontology. We are told by a Dutch website(b) that he thought Atlantis to have been situated on a submarine ridge stretching from Cape Verde to the Caribbean. This sounds like a revised version of the Atlantic landbridges concept that was popular with some scientists at the end of the 19th and beginning of the 20th centuries.
It is reported that he supported (1927) the idea of Cape Verde as the site of Atlantis, but I have been unable to confirm this. His adherence to Theosophy coloured his professional writings, for example with his claim that homo sapiens existed at the time of the dinosaurs. Similar ideas are promoted today by other theosophists such as John S. Gordon, who has written two Atlantis related books.
It has been claimed(a) that Dacqué wrote to Hitler in the 1920’s regarding some of his (Dacqué’s) occult ideas.
(a) https://www.freemasonrywatch.org/hitler_occult.html (offline June 2016) (see Archive 2795)
*(b) https://www.kunstgeografie.nl/atlantis/atlantis04.htm (offline Dec.’15) See: Archive 2796*
Michel de Montaigne (1533-1592) was an influential leader of the French Renaissance. He had studied law but abandoned it to devote himself to writing, producing three volumes of essays(a) on a wide range of subjects. For over four centuries Montaigne has influenced western philosophy and literature. Ignatius Donnelly ascribed the essays of Montaigne as well as the plays of both William Shakespeare and Christopher Marlowe to Francis Bacon!
In one of his essays, On Cannibals, Montaigne referred to Plato’s Atlantis and apparently accepted its reality. However, he did not express any opinion on the date of the lost civilisation or its location, apart from ruling out America, except to interpret Plato as saying that Atlantis was “situate directly at the mouth of the Straits of Gibraltar”. Modern commentators such as J. Warren Wells have also pointed out that in describing the location of Atlantis, Plato used the Greek word ‘pro’ means before and “that this in turn implies closeness.”[783.79] This conflicts with the idea that Atlantis was situated on or near the Azores, Canaries or Cape Verde archipelagos or further afield in the Americas or Antarctica.
Another small point is that Montaigne refers to ‘Africa and Asia combined’ (Timaeus 24e) rather than ‘Libya and Asia’ confirming that scholars in the 16th century understood that ‘Libya’ in Plato’s time had a broader meaning than just the territory west of Egypt.
Louis Germain (1878-1942) was a French zoologist who was among a number of commentators during the early part of the 20th century that identified Atlantis as a continent in the Atlantic,*[connected to the Iberian peninsula and what was later known as Mauritania in North-West Africa together with the Azores, Canaries and the Cape Verde archipelagos. He based his views on a study of molluscs on those islands as well as his suggested ancient links with the European and African mainlands.*]Improved geological and bathymetric studies gradually led to the abandonment of these ideas. Pierre Termier, a geologist, quoted Germain’s work to reinforce his own view that Atlantis had been located in the Atlantic.