by William J. Bahr
William J. Bahr: IBEX Systems Page 1 4/17/2020
Abstract: Bastille Measurement:
Resurrecting the Dimensions of Despotism
This article is about an architectural investigation of the Bastille’s
measurements. Before writing a book involving the Bastille [George
Washington’s Liberty Key: Mount Vernon’s Bastille Key – the Mystery
and Magic of Its Body, Mind, and Soul], I could find no written
descriptions of its height, length, and width. My first effort found
architectural drawings of the Bastille upon which I overlaid “tape
measures” developed by Photoshopping extended (end-to-end) scales.
Subsequently, I discovered three modern French authors who had made
assertions regarding the Bastille’s measurements, which were
significantly different from mine. To bolster my contentions, I found
additional Bastille drawings, these with partial measurements called-out
(annotated), which I added together to come to total measurements.
Unable to make an on-site survey of the street paver outlines of the
Bastille at the Place de la Bastille, Paris, France, I used Google Earth for
a GPS survey. Consolidating and integrating my efforts, I offer my
Bastille measurements with interesting comparisons to the Lincoln
Memorial and the Chateau de Tarascon.
©William J. Bahr 2020
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In 2014, in preparation for writing a book on Mount Vernon’s Bastille
key, I was challenged to determine why the Mount Vernon key was the
“main key” to the Bastille, as asserted by the Marquis de Lafayette, who
had gifted the key to George Washington in 1790. As I found little
information in English available at the time about where the door was
that the “main key” might have fit, I began an architectural investigation,
part of which involved determining the size of the Bastille. In doing so, I
became aware of significant discrepancies between its described and
The Bastille’s construction began in 1357, while its destruction began
432 years later, almost immediately after the Storming on 14 July 1789,
with subsequent development, both private and public, over the site. As
I could not easily find any written descriptions of the Bastille’s size,
especially in terms of the customary height, length, and width, I searched
on-line and discovered a number of the Bastille’s available engineering
diagrams completed before its destruction. These diagrams were made
by demolition manager Pierre-Francois Palloy, architect Etienne-Louis-
Denis Cathala, and engineer A.J. Mathieu. On each of these diagrams of
varying detail, I noticed scales, which were somewhat hidden, as the
drawings were much-reduced in size for on-line viewing. Subsequently,
I came upon high-definition versions of these drawings, which provided
better visibility of both the scales and the building. I then made multiple
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duplicate copies of the scales, which I Photoshopped together end-to-end
to make “tape measures.” Overlaying these “tape measures” upon the
“magnified” high-definition diagrams, I was thus able to determine the
building’s dimensions. As the scales were in pre-revolutionary French
toises, which I will explain later, I converted the measured toises to their
modern equivalent in English feet and meters. Because modern building
measurements usually involve descriptions of height, length, and width, I
made multiple measurements of the Bastille, which was not a rectangle
but a hexagon, This involved a number of measurement choices: height
(total or above the foundation, which itself involved a choice of whether
or not to include the basement – in six of the eight towers – and
remaining foundation); length (interior or exterior; curtain walls or
extending turrets; parapets or flared foundation; width (ends or middle,
each with the same choices as length).
Shortly after I published my book, Idiscovered more descriptive
information about the Bastille, which included short, written-in-French
dimensions, which were significantly different from mine and which did
not conform to the quick observation that the engineering drawings show
that the length appears to be twice the distance of the width at the ends.
The newly discovered written dimensions were first recorded in a
prestigious 1989 French book, to be followed up by a prestigious 2010
French book (with no direct citation of the 1989 book), and relatively
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recently cited by a 2016 French book (with no direct citation of either
previous book). Essentially all three books made the same assertion
about the Bastille’s dimensions, the first two describing it as a rectangle,
the last (presumably recognizing it was not a rectangle), as a
parallelepiped. Seeing that the supposed error in measurement would
continue with new publications and ever-multiplying citations, I decided
to investigate further and write this clarifying note. Certainly, the
Bastille, a symbol of one of the most important events in human history,
the beginning of the French Revolution, deserves fair representation,
especially as more and more publicity is given to annual massive
military parades for 14 July: “Bastille Day.”
First among the descriptions I observed, here is an English translation of
the French wording used by Nicolas Faucherre’s 1989 seminal work in
his book Sous les paves, la Bastille: “A first surprise is needed in view
of the images of the Bastille and the trace left on the pavers of the
current square: this monument with an immense reputation is a very
small thing, a modest rectangle 68 by 37 m [223 x 121 ft.] and 24 m
[78.7 ft.] high, placed to the rear of the enclosure which it was supposed
Second, here is an English translation of the French wording of the
Danielle Muzerelle’s 2010 book La Bastille: ou l’enfer des vivants: “The
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Bastille Saint-Antoine, now composed of eight towers, 24 m [78.7 ft.]
high, join curtain walls of the same height forming a rectangle of 68 m
[223 ft.] x 37 m [121 ft.], surrounded by a pit, offering a new
architectural model that was to meet a certain success in the next
Third, here is an English translation of the Jean-Christian Petifil’s
description in his 2016 book La Bastille: Mysteres et Secrets d’Une
Prinson d’Etat: “The Bastille had then reached its definitive form. It had
the appearance of an elongated parallelepiped, north-south, 68 m [223
ft.] long and 37 m [121 ft.] wide, slightly enlarged in its eastern part and
flanked by eight massive towers, connected by a crenelated curtain
equipped with a platform or walkway.”3
I also found dimensional descriptions of the Bastille from various reports
from prisoners, who, I presume, paced out the area or used some other,
unstated and likely inexact, means for their estimates: 100-foot high
walls, 90-foot long bridge, and various dimensions for several interior
In addition to a drawing made by Lieutenant Colonel Jean-Baptiste-
Claude Larcher d’Aubancourt in 1766, which I overlaid with extended
scales, I also came upon high-definition images of drawings Mathieu
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made of the Bastille with actual measurements called-out (annotated). I
added up the partial dimensions of the various building components of
the irregular Bastille and converted them into English and metric
equivalents to arrive at the total height, length, width dimensions
typically used nowadays to compare building dimensions. As the
Bastille was irregular, both outside and inside, there were no simple
height, length, and width measurements published while the building
existed, as there likely was little interest at the time to compare the
Bastille to other buildings.
Twice I also tried to have colleagues take some tape measures and visit
the Place de la Bastille, Paris, France, to measure the street paver
outlines of the Bastille (residual foundation ruins beneath the pavers).
Unfortunately, due to major construction and traffic at that location, they
were unable to use their tape measures to conduct a site survey. As a
result, I then used Google Earth to locate those street pavers outlining the
portions of the Bastille that are not covered by buildings and used the
Google Earth measurement tool to determine the length of the Bastille.
Finally, with my measurement results in hand, I contacted Professor
Nicolas Faucherre, the author of the 1989 seminal work, done on the
200th anniversary of the 1789 Fall of the Bastille, and to whose
dimensions estimate the subsequent authors apparently referred. I asked
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him how he came by those dimensions. He told me that, in a recent
move to his new academic position, he did not have all his old materials
and that his memory has faded after 30 years of his book’s publication,
when it was first asserted that the Bastille was a rectangle of 68 m [223
ft.] by 37 meters [121 ft.], with height of 24 meters [79 ft.]. He did
recall, however, that there were contradictions between the Bastille’s
dimensions as he saw them and its physical remnants. He also
congratulated efforts to measure the Bastille with modern methods of
In reviewing the dimensions previously given by the other authors, I saw
a relatively high degree of ambiguity. They didn’t say at what points the
measurements were made, especially with the allowances for where
(interior/exterior wall, base, or tower, etc.). Certainly, the building was
irregular. To call it a rectangle is somewhat misleading.
Given the details (later in this paper) of the diagrams made by the four
engineers/architects (d’Aubancourt, Palloy, Cathala, and Mathieu), one
will note my “tape measure” interpretations of their measurements
agreed with each other on length and width dimensions between 93%
and 100% of the time. One could, therefore, take a broad view and say
that they generally all agreed with one another, at least before taking into
account that Mathieu provided detailed information about the added
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“flare-outs” (for stability) of the Bastille’s parapets and base/foundation.
As well, Mathieu’s added dimension of height allows one to see the
different measurements of length and width at various heights, as
compared to the other measure-takers. Since Mathieu’s measurements
appear to be the most detailed and presumably the most careful, I viewed
him to be the most accurate of the Bastille measure-takers and gave his
dimensions more weight in coming to my own estimate of the Bastille’s
Let me say that it is not always easy to judge building dimensions, as
evidenced by modern-day disputes over what is the floor-space in a
house or which is the tallest building in the world. So I was left with
subjectively defining an “impression” of a building that had some degree
of irregularity. As far as building “impression,” the Bastille defies
easy/simple categorization. I knew that the Bastille, as regards length
and width, was an irregular structure, not rectangular but with at least six
distinct sides, with eight towers jutting out from the walls. Height of
modern buildings is currently determined not by “ornamentals” but
building design. So, as far as length and width, I decided that the
Bastille’s towers were not “ornamentals” but fair additions to the
Bastille’s mass, dominating and impressing enough to enlarge the length
and width dimensions. One can also see from the diagrams below that
the battlements jutted or flared out, just as did the base (perhaps a better
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term than foundation). For the most part, flaring and parapet dimensions
were not “called-out” or annotated in the diagrams. From close
inspection of the diagrams, however, one can observe that flaring adds 4
feet to the dimensions, while parapets add 3 feet. My rough or rounded
numbers try to take this into account, leaving a physical impression one
can use when comparing the Bastille’s length and width to that of other
As for the Bastille’s height, the building’s modification over time from
its original (stand-alone) two towers to include six new towers results in
a split-level configuration with a follow-on dimensional debate,
especially as regards the base. I saw that perhaps half the base height
included the cellar dungeons. As well, the base (approximately 20 ft.
high/deep) was exposed when the moat was not filled with water.
Noteworthy is that the moat was dry at the Storming of the Bastille and
that a man, trying to get a note from the Bastille, fell off the bridge and
broke his arm when he hit the bottom of the 26-foot “deep” dry moat.
So, with an often-empty moat, I decided the base part was part of the
height measurement, which, including the remaining 80-foot walls, thus
makes the Bastille’s height 100 ft.
Thus, I decided in favor of the maximum impression given by the
building, both in terms of height, length, and width. This means my
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measurements include the base and the walls (but not the several
guardhouses atop the walkway) in the height, and the maximum footprint
of the towers (with flare) in the length and width. My dimensions differ
substantially from the earlier authors.
Here is my assessment of the Bastille’s actual dimensions: The Bastille's
maximum outside dimensions (size), measured at the building's base:
approximately 260 feet long, 130-150 wide (ends, middle), and 100 feet
high. The base (the exposed foundation), which was sometimes covered
with moat water, was 20 feet high, with walls being 80 feet, making the
total height 100 feet. This maximum dimension takes into account the
protrusions of the towers and their battlements/parapets, as well as the
widened/flared footings at the base. The building was irregular, more of
a hexagon than a rectangle, hence the difference between middle and
ends. It is possible that some would want to look for dimensions just at
the Bastille’s interior; however, that itself was also irregular, with the
addition of various additions and apartments.
Again, I arrived at the above dimensions by consolidating and
integrating several measurement methods: 1. Taking the original, high-
(d’Aubancourt/Palloy/Cathala/Mathieu) drawings/diagrams and
overlaying upon them “tape measures” made from their extended scales
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(duplicated and add together end-to-end via Photoshopping). 2. Taking
additional Bastille drawings, these with partial measurements called-out
(annotated), which I added together to come to total measurements. 3.
Using Google Earth and its measurement tool to measure the outline of
the Bastille at the Place de la Bastille, Paris, France. I converted the
resulting measurements from pre-revolutionary French measurements of
toises, pieds du roi, and pouces into modern measurements of feet and
To introduce and explain my data, let me start by observing that in 1766,
Lieutenant d’Aubancourt, the Royal Corps Engineer in charge of the
Bastille, made a drawing of the Bastille. Then in 1789, after the
Storming of the Bastille, six inspectors, 3 of whom were architects, were
appointed by the municipality of Paris to supervise the demolition. Here
are some of their names:
1. Pierre-François Palloy (Construction/demolition)
2. Etienne-Louis-Denis Cathala (Architect)
3. A. J. Mathieu (Engineer and mechanic under architect Edme
4. M. Vienne (Bastille inspector -- Presumably pacing around the
Bastille between 1 November 1789 and 1 November 1790, he measured
a circumference exterior to the walls and towers of 160 toises = 1023 ft.
This compares to at most 820 ft. for the perimeter as measured on the
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drawings of the previously named individuals. I presume that Vienne
must have measured around the outskirts of the fallen debris.)5
Here below are some of their diagrams with my extended scales. Note
that the original scales from which I made the overlaid extended scales
were made are usually located in the lower left-hand corner of the
diagrams. Also, please note that a toise is a near-equivalent to an English
fathom (6 ft. finger-tip to finger-tip distance between outstretched arms).
1toise contains 6 pieds du roi (French royal feet), each of which
contains 12 pouces (royal inches; pouce is French for “thumb,” measure
of thumb at base).
1 Toise = 6 pieds du roi = 6.39 ft. = 1.95 m
1pied du roi = 12 pouces = 1.07 ft. = 32.48 cm
1pouce = 12 lignes = 1.07 in. = 27.07 mm
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Bastille. Diagrams from d’Abauncourt, Palloy, and Cathala with
extended scales overlaid. Sources believed to public domain.
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Note that Mathieu’s drawing below (with my extended scales overlaid) is
the most detailed.6Please observe the transposition of dimensional
nomenclature from width to length and from depth to width. Also note
base/foundation is integrated with the building. It’s difficult to see
base/foundation measurements (nominally 20 ft.) from above, and there
are interpretation problems due to multi-levels.
Bastille. Diagram from Mathieu with extended scales overlaid.
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Below are diagrams from Mathieu, these with distance annotations.
Bastille. Diagrams from Mathieu which include call-outs (annotations)
of partial dimensions. Courtesy CNMHS and BNF.
One of the diagrams above shows the height of the Bastille of 96 pieds
from top (parapet) to bottom (base); also the 16 pieds height for the base.
It also shows the flare of the parapet beyond the wall of 3 pieds; and the
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flare of the base of 4-5 pieds. Thus, one could add 4 pieds du roi to each
end or a total of 8 pieds x 1.07 ft./pied (8.56 ft.) for parapets/flared
foundation extensions added to length and width dimensions. Note the
old towers (the original two larger, projecting towers) versus the new
towers (all others) were 16 pieds in radius versus 15 pieds, respectively.
Adding up the called-out partial dimensions from Mathieu results in the
Dimensions from Mathieu from diagrams with measurement call-outs.
Note final columns with extensions added.
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Here below is a Google Earth view of the Bastille.
Bastille Paver Outline. Google Earth view of Bastille pavers with its
measured length at the Place de la Bastille, Paris, France.
My GPS survey via Google Earth yielded a 248 ft. length, as measured
from end to end of the paver outline. With views changing over time,
GPS measurement of the Bastille is sometimes difficult, as the Place de
la Bastille is often filled with traffic, obscuring (seasonal) tree growth, or
construction. As a calibration, my Google Earth GPS survey of my
driveway yielded only 2-inch difference in measured width of 30 ft (a
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difference of one-half percent). It should be noted that architects often
use Google Earth estimates when site access is difficult.
Here below are the results of my Bastille measurement efforts, with
dimensions from extended scale measurements or totaling call-outs of
partial measurements, and the comparison with the previously published
version of dimensions.
Comparison of measurements. Results in meters is similar for that in
feet. 1 m = 3.28 ft. 1 ft. = .30 m
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In many respects, my measurements for the Bastille were amazingly
similar to those of the Lincoln Memorial (in Washington, DC) and the
Chateau de Tarascon (near Marseille, France).
Bastille and Lincoln Memorial. Drawing of Bastille, courtesy of Nicolas
Melnyk with my measurements overlaid. Also photograph of Lincoln
Memorial with rounded measurements from the National Park District
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Here is information about the Lincoln Memorial from the National Park
Service:7“Height of building: 79 ft. 10 in. from foundation top; 99 ft.
above grade at foot of terrace walls.” “Total width [length] of building
north to south: 201 ft. 10 in. at widest point.” “Total depth [width] of
building east to west: 132 ft. at widest point.” I rounded these
measurements to 100 ft. high (80 + 20 ft.), 200 ft. long., and 130 ft. wide.
Here are other comparable aspects of the Bastille and Lincoln Memorial:
Bastille: 232 St. Antoine St., Paris, France.
Lincoln Memorial: 2 Lincoln Memorial Circle, Washington, DC.
The Bastille originally had an east entrance, just as the Lincoln Memorial
currently does (the Bastille’s east entrance was later blocked). The
Bastille had the same height and same width (at endpoint) as the Lincoln
Memorial, but the length was 30% longer. Site acreage was the same at
6.5 acres. One can go to south end of Lincoln Memorial to get
impression of Bastille size when the Bastille’s pedestrian gate (the gate I
sought for the “main” Bastille key) is viewed from the south. One can
look off to the right (east) to the Washington Monument (555 feet tall)
for a distance between Bastille and Paris City Hall impression. Both the
Bastille and the Lincoln Memorial were each 12 miles away from the
home of the chief of state (Versailles and Mount Vernon, respectively),
over a river, & southwest.
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Below is a drawing and a photograph of the “Brother to the Bastille,” the
Chateau de Tarascon near Marseille, France.
Chateau de Tarascon, Tarascon, France. Drawing with extended scales
and photograph with Bastille measurements overlaid. Photograph
courtesy of John Egan.
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1. Nicholas Faucherre. Sous les pavés, la Bastille, Archéologie d'un
mythe révolutionnaire (Paris, Caisse Nationale des Monuments
Historiques et des Sites, 1989), 46.
2. Danielle Muzerelle. La Bastille: ou l’enfer des vivants (Paris: BNF,
3. Jean-Christian Petitfils. La Bastille:Mystères et secrets d'une prison
d'Etat (Paris: Tallandier, 2016), 21.
4. Fernand Bournon. La Bastille, Histoire Et Description Des
Bâtiments.--Administration.--Régime de la Prison.—Événements
Historiques (Paris: Imprimenerie Nationale, 1893), 210-11.
5. Primary among several descriptions is the one made by Simon
Nicolas Henri Linguet. Memoirs of the Bastille: The Annotated
Version, ed. Jim Chevallier (San Bernardino, CA: Chez Jim
Books, 2005), 146.
6. A. J. Mathieu. “General Plan of the Bastille.”
required for zooming at http://www.regards.monuments-
7. Lincoln Memorial Building Statistics.