I have had a pamphlet for a very long time by R.I.L.K.O., Research into Lost Knowledge Organisation, founded by Keith Critchlow (and others,) who was also the lead author of CHARTRES MAZE: A Model of the Universe. It discusses the problems we may have in comprehending antiquarian matters such as how and why labyrinths featured at all in "Gothic" (i.e. New Style) cathedrals, most of these features having been ripped out during the Revolution, and leaving us with perhaps the best in Chartres, the best cathedral of the early period. The paper discusses the precedents for such designs in the game of Hopscotch so as to bring out the possibility of cosmological schemes having been placed into games, perhaps to save doctrines and hence constituting "Lost Knowledge". One has to compare the Chartres eleven layer labyrinth with the more famous seven-fold labyrinth, found throughout Europe but famously in Crete as the Minotaur lair. Unlike a maze, a labyrinth has only one path into and the same path out of the centre, like life itself. The pamphlet's main payload is the overlay of the ancient geocentric models of the planetary system surrounding the earth, as known to the Greek world, into which the soul descends from the sphere of the fixed stars and "lands", incarnate on earth, only to hopefully reverse the same path with the help of some knowledge of the topography of this planetary model.
Thus, the labyrinth could refer to a model of the planetary world and originally designed to function similarly as a Pyramid Text or Book of the Dead. But usage at Chartres, rebuilt after 1200, was similar as today as it functioned as a part of a large scale pilgrimage network in which the journey into and out of the labyrinth was equated to a pilgrimage to Compostella (interestingly, "to the stars") or even Jerusalem, especially as Jerusalem was once more lost to Christendom.
The pamphlet makes an aside concerning the location of the labyrinth within the floor plan of the cathedral, that relates it to the location of the famous rose window in the west, between the towers.
The clue to the placing of the maze and the length of the nave came unexpectedly from the difference in height of the two towers of the West front. Facing the west front from outside one can clearly see a crescent moon surmounting (as a weather vane) the shorter tower on the right. In the same way, on the later, more ornate tower on the left one can see a solar image as weather vane. This might have been ignored as 'decorative' if [it was not] the fact that from ground level to the focus of the angle of the spire below the solar vane height measured 365 feet. This latter idea came from Christopher Wren's same predeliction by placing the apex of St. Paul's Cathedral 365 feet above the pavement of London.
However, this "idea" of the northern "solar" tower being 365 feet high proves to be a red herring. Wikipedia gives the height of the north-west "solar" tower as 113 metres (371 ft) (the south-west tower as 105 metres (344 ft)). It is the 344 foot tower that is clearly signed with a lunar weather vane and if one divides its height of 344 feet by the 354.368 days of the lunar month, one obtains the Roman foot in its lesser "geographical" microvariation, i.e. a foot of 0.971003 feet. To obtain a better idea of the relative height of the "solar" tower, one needs to establish the objective ratio between the balls that sit atop the towers' fleched roofs as being 1.085, using a plane drawing of the western prospect.
The above height of 371 feet can be corrected to 373 feet which, divided by the same roman foot identifies the other type of lunar year, of 13 lunar months in 384 days. This year was called the Embolismic Year which had a calendric usage in the medieval, to provide an intercaliary month so that after three solar years, the lunar calendar would resynchronise with the solar calendar. This is the exact same periodicity found in the southern kerb of the Quadrilateral of Le Manio (4000BC), in which 12 + 12 + 13 lunar months equal 37 whereas three solar years equal 37.1 lunar months. Only in that sense is the north tower solar, since its height signifies the embolistic year. This will have consequences for any correlations between the western towers and the Gothic floor plan.
This procedure also allows us to know the relative height of the rose window which the pamphlet correlates with the location of the labyrinth. The centre of the rose window is 106.7638 roman feet above the common datum, the pavement. This is exactly 47 lunar months (1387.94 days) divided by 13, i.e. divided by the embolistic month, which gives 106.764 days. Five times 47 is the 235 lunar months in the 19 year anniversary of sun and moon called the Metonic period.
Armed with these now correlated figures and units one can look at the location of the towers and rose window on the floor plan of the cathedral.
One can see that the centre of the rose window is indeed reached from a datum of the inner surface of the walls of the inner towers. One can then use that datum to project north east (noting the angle of cathedral), the two towers whose difference is the depth of the Rond ("round") sanctuary whilst the "moon" tower consumes the whole distance from the threshold of the cathedral, through its nave, the crossing and the choir. The number of pillars either side of the route number twelve, symbolising the number of lunar months in the lunar year. This diagram compares with that of John James whose figure 69 "The Easter dating set into the cathedral" is shown below.
figure 69 "The Easter dating set into the cathedral" of Master Masons of Chartres by John James, West Grinstead, 1982, page 111.
Here, James recognises a geographical royal foot (353mm or 1.158583 ft) as encoding the key lengths of the solar, lunar and embolismic years and ties the importance to the infamous difficulty of the calculation of Easter chosen by the first council of Nicaea in 325 to solve the "controversy between those who advocated independent computations, and those who wished to continue the custom of relying on the Jewish calendar", which was purely lunar. The date came to be defined for the western church as the first sunday (7 day week) after the first full moon (lunar calendar) after the spring equinox (solar calendar).
To conclude, there has been some interest as to how long the journey is through the labyrinth. A very helpful blog page exists at https://blogmymaze.wordpress.com. LabyrinthBlog (by Erwin Reißmann (D) and Andreas Frei (CH) ) says
"According to my calculated alignment I get a path length of 263.05 m. The beginning of the line is the intersection of the path axis with the outside radius of the lunations. John James stated 261.5 m as path length, Robert Ferré states 261.55 m, Jeff Saward has calculated 262.4 m (with the beginning further inside), Hermann Kern reported 294 m. I would like to say the path length is 263 m. This is an integer. And the sum of the digits is 11, such as the 11 circuits of the labyrinth."
However, using the 0.971003 ft, unit used in the towers, the labyrinth length appears to be 888 feet. This ideal would then be 262.8 metres. On Wikipedia one reads
"In Christian numerology, the number 888 represents Jesus, or sometimes more specifically Christ the Redeemer. This representation may be justified either through gematria, by counting the letter values of the Greek transliteration of Jesus' name, or as an opposing value to 666, the number of the beast"
This picture from above shows the third pair of columns astride the centre of the labyrinth.
56 Candles have been placed on every other "lunation" cog,
demonstrating the 112 cogs as 16 times seven.