The Newsletter of Hopewell Archeology
in the Ohio River Valley
Volume 6, Number 2, March
2. Design and Layout of the Newark Earthwork
By William F. Romain, Ph.D.
click on image to enlarge
The Newark earthwork complex is the largest
and most complicated geometric complex of
its kind in the world. (Figure 1) shows the
complex as represented by Squier and Davis
(1848: Pl. XXV).
(Figure 2) shows what remains of the complex
today – i.e., the restored Octagon
and Observatory Circle and the Great Circle.
Also shown is Geller Hill. The likely location
of the Great Hopewell Road (Lepper 1995)
and Wright Square are also indicated, based
on surviving remnants and aerial photographs
Looking at the Squier and Davis map, a casual
observer might think that the large geometrically
shaped earthworks, such as the Octagon,
Great Circle, and Wright Square were arbitrarily
located on the Newark landscape. As demonstrated
below, this was not the case. Each earthwork
is situated at precise coordinates and
in a fashion that follows an internally
1. Squier and Davis’s (1848: Pl.
XXV) map showing the Newark earthwork complex.
on image to enlarge
2. USGS 7.5-minute series topographic map
showing part of the Newark earthwork complex.
on image to enlarge
With reference to (figure
3, right), the following exercise
shows how the Newark complex might have
designed and laid-out.
1. Point A is the apex
of Geller Hill. Draw line A-B at an azimuth
of 52°.2, which is equal to the moon’s
maximum north rise position as viewed
from the top of Geller Hill (A.D. 100,
limb tangency, apparent horizon elevation
of 0°.5, corrected to 1°.34.)
2. Draw an arc having a
radius of 7 OCD from point A. (One OCD
is equal to 1,054 feet – which is
the diameter of the Observatory Circle – see
Hively and Horn 1982.)
3. Schematic plan showing geometric and
astronomic relationships among various
features of the Newark earthwork complex.
3. Construct a circle having
a diameter of 1,178 feet - equal to the
size of the Great Circle. (Note that the
diameter of 1,178 feet for the Great Circle
is equal to the hypotenuse of a right triangle
whose sides are equal to 1 OCD and ½ OCD,
4. Draw line, D-E. Make
line D-E, 7 OCDs in length. Situate line
it is perpendicular to lunar azimuth
line A-B, bisected by line A-B, and 589
from the 7 OCD radius line as measured
A-B. The distance of 589 feet is one-half
of the Great Circle diameter – which
in step 3, was shown to derive from the
OCD unit of length.
5. Position the center of the Great Circle
on the 7 OCD radius line so its circumference
meets line D-E at D.
6. At point E, construct a square having
sides equal to 1 OCD. Orient the square
so its diagonal falls on line D-E.
7. Construct an octagon around the square.
Do this by drawing a series of arcs, each
having a radius equal in length to the
diagonal of the square. (Diagonal of square
= 1,490 feet) Use each of the square’s
corners as the center for each arc. Connect
the intersection points of the arcs by
straight lines, thereby creating an octagon.
8. From Octagon point F, draw a line perpendicular
to line D-E. Label this new line F-G. Line
F-G is parallel to line A-B. Thus the Octagon
is lunar-aligned. (See Hively and Horn
 for a further discussion of this
9. Locate the center of the Octagon and
label it point H.
10. Locate points on line F-G that are
1 and 2 OCDs, respectively, from point
H. Label these points, I and J.
11. Construct a circle on line F-G, using
points I and J to establish its diameter.
The diameter of the resulting circle will
be 1 OCD - equal to the diameter of the
12. Establish the center of the Observatory
Circle. Label the center of the Observatory
Circle, point K. From point K, draw an
arc having a radius of 7 OCDs.
13. Likewise, from point E on the Octagon,
draw an arc having a radius of 7 OCDs.
Mark the point where the two arcs intersect,
14. Construct the Wright Square, oriented
to the cardinal directions, using point
L to situate the south corner of the Square.
Note that each side of the Wright Square
is 925 feet in length. This length is related
to the OCD in the following manner. As
mentioned, the diameter of the Great Circle
is equal to the hypotenuse of a right triangle
whose sides are 1 OCD and ½ OCD,
respectively. The diameter of the Great
Circle therefore is 1,178 feet. From this
it follows that the circumference of the
Great Circle is 3,700 feet. If the Great
Circle circumference is divided by 4, the
result is 925 feet. Thus, the 925-foot
length is related to the OCD.
15. The azimuth and location of the Great
Hopewell Road are established in the following
way. From point A on Geller Hill, draw
a line to point N on the Octagon. The azimuth
of this line is 26°.2. From point N, draw
a line 1 OCD in length perpendicular to
line A-N. Mark the end of this line, point
O. The reciprocal of 26°.2 (the azimuth
of line A-N) is 206°.2. From point O, extend
a line for a distance of 13,040 feet. along
the azimuth of 206°.2. This line represents
the length and azimuth of the Great Hopewell
Road as far as Ramp Creek.
on image to enlarge
||The above representations
are idealized geometric constructions.
The actual Newark
earthworks vary in a few minor respects
from the ideal – see (figure
The Great Circle earthwork, for example,
is not quite a perfect circle. Its diameter
varies between 1,163 feet and 1,189 feet,
for an average of 1,176 feet (Thomas
1894:462). So too, certain of the actual
Octagon’s walls vary from the geometric
ideal in both length and azimuth - possibly
to bring the walls in closer alignment
with significant lunar positions. The
azimuth of the major axis through the
actual Octagon and Observatory Circle
extends along an azimuth of 51°.8, while
the geometric ideal, based on the moon’s
calculated azimuth is 52°.2 - for a difference
4. Ideal geometric design shown in figure
3 overlaid onto USGS 7.5-minute series
map for the Newark area.
Thomas (1894:466) gives
the lengths of the Wright Square walls
as 926 and 928 feet – which differs
by 1-3 feet from the geometric ideal
of 925 feet. Also, the major axis of
the Wright Square is skewed about 2°
from the ideal, perhaps taking into
account ground observations referenced
distant horizon elevation.
As for the Great Hopewell Road, remnants
are still visible today at point O.
These remnants are about 3 feet in
height, extend for dozens of feet,
and are located near the northeast
walls of the Octagon. Sections of the
south half of the Road can be identified
in early aerial photographs (Reeves
1936). Reeves’s (1936:fig. 4)
representation of the Road, drawn based
upon his aerial photographs, shows
the Hopewell Road intersecting a modern-day
road just south of the Newark-Heath
airport. From these data, the azimuth
of the actual Road can be plotted and
is found to be 206°.9. This differs
from the azimuth of 206°.2 for the
geometrically plotted Road by 0°.7.
Several conclusions derive from this
1. The location of each earthwork
is geometrically and astronomically
related and dependent upon other earthwork
components. Each earthwork is an integral
part of a larger design.
2. The entire complex is, in effect,
generated from Geller Hill – the
suggested axis mundi for the Newark
3. The complex was laid-out based
on the moon’s maximum north rise
point and multiples of the OCD unit
of length. The significance of the
lunar maximum north rise for the Hopewell
may have been based in the recognition
that that event defines a temporal
and spatial maximum in an 18.6-year
cycle. Maximum nodes in any cycle imply
a complementary opposite – to
include, for example, a lunar maximum
south rise. Notions of complementary
opposites, bilateral symmetry, and
cosmic dualism appear to have been
important to the Hopewell and are expressed
in a wide range of scales, from the
structure of their earthworks, to designs
incorporated in their artwork.
4. The most commonly used multiple
unit of length was 7 OCD. Seven is
considered an important number by many
Native Americans. In Indian belief
systems, the number 7 derives from
the 4 cardinal directions, plus the
center, zenith, and nadir.
Hively, Ray, and Robert Horn.
1982. Geometry and Astronomy in Prehistoric
Ohio. Archaeoastronomy (Supplement
to Vol. 13, Journal for the History
of Astronomy) 4:S1-S20.
Lepper, Bradley T.
1995. Tracking Ohio's Great Hopewell
Road. Archaeology 48 (6):52-56.
Reeves, Dache M.
1936. A Newly Discovered Extension
of the Newark Works. Ohio State
Archaeological and Historical Quarterly 45:187-193.
Squier, Ephraim G., and Edwin H. Davis.
1848. Ancient Monuments of the Mississippi
Valley; Comprising the Results of
Extensive Original Surveys and Explorations.
Smithsonian Contributions to Knowledge
Vol. 1. Washington, D.C.: Smithsonian
1894. Report on the Mound Explorations
of the Bureau of Ethnology for the
Years 1890-1891. In Twelfth Annual
Report of the Bureau of American
Ethnology. Washington, D.C.: Smithsonian
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