Further confirming Atlantis was the size of a continent, the account describes a large geographic feature existing in the midst of the island which is roughly the size of Great Britain. A geographic feature with key distinct attributes that readily made it the central focus in my search for Plato's Atlantis. That feature is an extremely large, uniquely rectangular plain, and Plato included a component which would prove an invaluable aid in narrowing down the search: Dimensions.
"The whole country was said by him to be very lofty and precipitous on the side of the sea, but the country immediately about and surrounding the city was a level plain, itself surrounded by mountains which descended towards the sea; it was smooth and even, and of an oblong shape, extending in one direction three thousand stadia, but across the centre inland it was two thousand stadia." - Critias 118a
"It was originally a quadrangle, rectilinear for the most part, and elongated; and what it lacked of this shape they made right by means of a trench dug round about it...and since it was dug round the whole plain its consequent length was 10,000 stades." - Critias 118c,d [Bury]
Yet, I was not the first to recognize the potential the unique layout of the Atlantis plain held in identifying the lost continent. For many decades the seemingly best geographic match for Atlantis and its unique plain was offered by another Atlantis theorist, Jim Allen. In the 70s Allen set out on his own search for the Atlantis plain ultimately linking it to the Altiplano, a large plain located high up in the Andes Mountains in the western region of Bolivia, South America. The plain possesses the requisite rectangular shape and is clearly surrounded by mountains, but more importantly Allen had boldly pushed past the bounds of established history favoring geographic conformance with Plato's description of a continent beyond the Mediterranean.
South America and Jim Allen's posited site of the Atlantis plain high in the Andes Mountains, the Altiplano.
So in regard to geographic accuracy, Allen's Atlantis theory has sat at the forefront for quite some time, setting the bar for others like myself to clear. The following analysis of the Altiplano site will reveal where that bar actually sits and provide perspective on the challenges involved in locating and identifying the ancient plain of Atlantis. (More information can also be found at Allen's website.)
The claim is made that the Altiplano matches the Atlantis plain's 2,000 by 3,000 stade (230 by 344 mile) measurement, but does so with some major concessions. Because the Bolivian Altiplano is substantially smaller than the Atlantis plain, a theoretical stade has been adopted measuring roughly half the length of the ancient Greek and Egyptian stades, but even with this posited half-stade the Altiplano does not appear to legitimately achieve a 2,000 by 3,000 proportion.
The image below is a reproduction of Allen's assessment of the Altiplano as a 2,000 by 3,000 stade rectangle utilizing a stade measuring 330 feet versus the Greek stade of 606 feet. The plain's 13,000-foot contour is outlined in yellow while the plain's interior 12,000-foot contour is outlined in dark blue. Allen has chosen the placement of the 2,000 by 3,000 stade rectangular channel of water said to define the plain by utilizing the 13,000-foot elevation for the lateral measurement while utilizing the 12,000-foot elevation for the vertical measurement.
There are several obvious problems with this layout. First among them is the arbitrary and inconsistent selection of contours within the plain to achieve a 2,000 by 3,000 ratio. Secondly, it is highly doubtful that the ancient people providing the measurements of the plain were aware of nonphysical 1,000-foot increment contour lines not only because these are based on modern measurements, but also because an individual on the ground standing on the 12,000-foot contour would have no means in which to discern the invisible delineation, but instead would typically see that the plain extended out in a gradual drop or rise in all directions like most other locations in the midst of the plain.
The only possible exception in this on the ground observation would be the actual existence of the rectangular channel or ditch defining the plain's perimeter. This of course leads to our third issue with the site: to attain the rectangular channel, the Atlanteans would have been required to dig ditches through a hundred miles or more of mountainous terrain in the plain's western region.
A reproduction of Jim Allen's layout of a 2,000 by 3,000 half-stadium rectangle on the Altiplano. Not only does this layout abandon the account's standard sized stadium for an obscure half-stadium measurement, but it also arbitrarily jumps between contours of 13,000 feet (yellow boundary) and 12,000 feet (dark blue contour) in order to allow the Altiplano to conform to Plato's dimensions. Further complications arise in the layout of the rectangular ditch that was said to define the plain. Much of it would have been dug through mountainous terrain in the west.
An oblique view of the Altiplano gazing northward, revealing the mountainous western region included within the plain of the Altiplano theory and the course the proposed rectangular ditch cuts through it.
Aside from the necessity to introduce a new measurement for the stade, the proposed site also necessitates the introduction of a mountain lake, Poopó Lake, as a third sea, although Plato's account makes absolutely no effort to distinguish or suggest any seas beyond two, the Mediterranean and Atlantic. This adjustment in interpretation was required because the original account places the sea very near to the plain. A hill which would be the site of the capital city having a diameter of 27 stades (3.10 miles), was said to lie 50 stades (5.7 miles) from both the plain and the sea, combined measurements which require the plain to lie within 14.5 miles of the sea.
"Near the plain again, and also in the centre of the island at a distance of about fifty stadia, there was a mountain not very high on any side (the site of the city)....And beginning from the sea they bored a canal of three hundred feet in width and one hundred feet in depth and fifty stadia in length, which they carried through to the outermost zone [of the city]." - Critias 113c, 115d
Poopó Lake is an endorheic basin having no outlets to a sea or ocean. During periods of excessive water flow from the north, which would have had to have been the norm in order to fill and maintain a navigable channel around the Altiplano, the lake spills out onto the Altiplano filling two large salt basins, Salar de Coipasa in the west and Salar de Uyuni in the south, but this direction of flow runs counter to the Atlantis plain. While water travels from Poopó Lake—the proposed 'sea'—past the city and onto the plain, according to Plato's account all the waters of the plain ran in the reverse direction, from the plain and into the sea near the city. Instead of a landlocked lake, it seems clear that the account is describing the common geographic dynamic of most low-lying plains whose waters originate and flow down from the mountains, run through or around the plain and inevitably empty into a true sea or ocean.
"[The ditch] was carried round the whole of the plain, and was ten thousand stadia in length. It received the streams which came down from the mountains, and winding round the plain and meeting at the city, was there let off into the sea. Further inland, likewise, straight canals of a hundred feet in width were cut from it through the plain, and again let off into the ditch leading to the sea." - Critias 118c,d
Note too that none of the canals are said to directly empty into the sea, but instead they flowed out into the plain's perimeter ditch and then emptied into the sea. This suggests that the sea did not exist inside the plain's perimeter as is the case of the Altiplano and again gives every indication that it is referring to a true sea existing beyond the plain.
The site also falls short regarding the full layout of the plain's surrounding mountains:
"The country immediately about and surrounding the city was a level plain, itself surrounded by mountains which descended towards the sea. This part of the island looked towards the south, and was sheltered from the north. The surrounding mountains were celebrated for their number and size and beauty, far beyond any which still exist." - Critias 118a,b
This passage describes a plain which was enclosed on three sides, but open towards the south. The illustration below of an enclosed courtyard perfectly illustrates an enclosed area looking to or open toward the south and sheltered from the north. The Altiplano, however, remains completely surrounded on all four sides by mountains; essentially sheltered from both the north and the south.
This image depicts an enclosed courtyard, which similar to the Atlantis plain is open or "look(s) towards the south, and (i)s sheltered from the north" while also "looking towards the sea." This layout stands in contrast to the Altiplano in the Andes which is entirely surrounded by mountains, sheltered from every direction while the sea sits within the northeastern portion of the plain.
Also note this parallel passage:
"Looking towards the sea, but in the centre of the whole island, there was a plain which is said to have been the fairest of all plains and very fertile." - Critias 113c
There is some confusion among interpretations regarding the phrase "looking towards the sea," but contextually, like the phrase "looked towards the south," it would appear to be describing the plain. In other words, "In the center of the whole island there was a plain looking or facing towards the sea." It is hard to derive any other meaning, and together the two phrases assert that the plain was open toward or faced the sea in the south. Here again we see that the Altiplano fails by locating a sea in the east and as stated above incorrectly inside the boundaries of the plain.
Then there are also a few issues seen in the proposed site of the capital city at Pampa Aullagas. Like the sea, this theory incorrectly locates the city within the boundaries of the plain. The city's stated location was 50 stades (5.7 miles) outside the plain, whereas the proposed site of the city in this theory locates it on a hill over 200 stades (23 miles) inside the plain.
Near the plain again, and also in the centre of the island at a distance of about fifty stadia, there was a mountain not very high on any side." (The site of the capital city.) - Critias 113c
Even more problematic, the concentric rings of water that were said to define the city are theorized to have existed in sand filled contours set into the side of the hill with the land in between forming the concentric rings of land, but these would actually have been partial bands of land and water and not the full circular rings described. The original account makes clear that these were "circles" of water believed to be natural formations isolating the ringed islands and rendering them inaccessible except by boat. This runs counter to the proposed bands at Pampa Aullagas, which would allow the central island where the acropolis was located to have been fully accessible by land in the south.
"Breaking the ground, enclosed the hill in which she dwelt all round, making alternate zones of sea and land larger and smaller, encircling one another; there were two of land and three of water, which he turned as with a lathe, each having its circumference equidistant every way from the centre, so that no man could get to the island, for ships and voyages were not as yet." - Critias 113d,e
Further each band on the proposed site is located sequentially at higher levels as they approach the proposed location of the acropolis on the hill's peak. If the Altiplano were flooded to a depth to fill the upper ring, the lower rings would be flooded over and not exist. Not to mention nearly all of the Altiplano would have been a lake and no longer a plain.
Pampa Aullagas on the Altiplano; the proposed site of the ringed capital city of Atlantis. Contradicting Plato's description of rings of water fully encircling islands only accessible by boat, the site at Pampa Aullagas proposes bands of water and allows access to the central island by way of land in the south.
Perhaps we can imagine that the upper rings were artificially filled with water, but this too is problematic since according to the account the Atlantean ships of war were able to sail not only from the sea to the outer ring of the city, but also between rings of water with access to the central island where the palace was located along with docks full of warships and naval stores.
"They divided at the bridges the zones of land which parted the zones of sea, leaving room for a single trireme to pass out of one zone into another, and they covered over the channels so as to leave a way underneath for the ships; for the banks were raised considerably above the water." - Critias 115e
"The docks were full of triremes and naval stores, and all things were quite ready for use. Enough of the plan of the royal palace. Leaving the palace and passing out across the three..." - Critias 117d
Yet with this proposed site the rings are at levels separated by 50 to 150 feet in elevation which would have required locks to move between channels, which would in turn create further complications in maintaining the water level in the upper ring.
The only possible solution is to accept that the account was not exaggerating when it states that "the banks were raised considerably above the water." In this configuration the proposed rings or channels of water would have been excavated to a common depth with covered channels or tunnels created "so as to leave a way underneath for the ships." The uppermost inner ring would have been excavated to a depth of about 350 feet. This would have allowed the plain to remain an unflooded plain and still facilitate ship access between channels, but it seems highly doubtful that these sand-filled contours were excavated to such an extent and based on the natural occurrence of sand-filled contours on other hills nearby, it is almost certain that naturally formed and intact solid bedrock lie just feet below the surface proving no such excavation ever took place.
This image of Pampa Aullagas includes cutaway views of the proposed partial rings of water from the previous view. Note the required depth of each ring to reach a water level that would allow 'triremes' to move between each 'ring' as was claimed and at the same time leave the plain unflooded. Other hills in the vicinity exhibiting identical geomorphology where erosion and ancient flooding has formed sand beds in shallow recesses, suggest that it is more likely that solid bedrock lies just below the surface of the site's proposed bands.
All said, aside from being a rectangular plain surrounded by mountains, the Altiplano shares very little in common with the Atlantis plain. The isolated location of the plain and the unexpected introduction of a mountain lake as a third sea also creates a disjointed and confusing narrative, as the account restricts its detail of the Atlantean combatants to the 240,000 mountain men from the plain who apparently sailed about Poopó Lake in large 200-man warships, yet provides no explanation as to how these mountain men and their ships had access to the Atlantic or had acquired a mastery of the open seas.
"Of the combatants on the one side, the city of Athens was reported to have been the leader and to have fought out the war; the combatants on the other side were commanded by the kings of Atlantis...Let us give the precedence to Athens." - Critias 108e-109a
"And next, if I have not forgotten what I heard when I was a child, I will impart to you the character and origin of their adversaries." - Critias 112e
"I will now describe the plain...As to the population, each of the lots in the plain had to find a leader for the men who were fit for military service, and the size of a lot was a square of ten stadia each way, and the total number of all the lots was sixty thousand. The leader was required to furnish for the war...four sailors to make up the complement of twelve hundred ships. Such was the military order of the royal city-the order of the other nine governments varied, and it would be wearisome to recount their several differences." - Critias 118c-120d
Based on the figures above the 1,200 naval ships or triremes were manned by 200-man crews all sourced from the inhabitants of the plain. Also keep in mind that not only were the triremes said to have access to the city from a channel to the sea with many triremes filling the inner harbors, but the account also states that a multitude of merchant ships arriving from other regions filled the outer harbor.
"The largest of the harbours were full of vessels and merchants coming from all parts." - Critias 117e
All signs point to an ancient maritime empire with its capital city near the "true sea" and not a large naval contingency wielding power over the inhabitants of the Mediterranean from their high perch on an isolated lake in the Andes.
This evaluation should demonstrate the extreme difficulty of identifying and associating a real world plain with the Atlantis plain. It is not so surprising given the extensive set of restrictive parameters provided by Plato's account, comprising a complex matrix of geographic features with relative alignments to each other, alignments to cardinal directions, and finally dimensions of size and distance which are the most critical and extremely limiting qualifiers.
On the upside, due to the presence of such intricate detailing, the account's description should prove every bit as effective as using a physical map in locating and identifying the ancient plain and the long-sought continent of Atlantis. It is for all intents and purposes a treasure map in written form.