Figure1. View of the Serpent Mound tail illuminated by candles on 12-21-2014.
It was a spectacular evening as more than 1,000 people gathered for the annual candle lighting ceremony at Serpent Mound. Old friends met and new friends were made as people waited in breathless anticipation of sunset. As dusk turned to dark, the candles were lit and we watched - united in appreciation of the scene unfolding before us as the sun sank into the western horizon. In our experience of this event we knew that this celestial turning point marked the beginning of a new year - a year that promises hope and renewed life.

Figure 2. Photos of some of the people who gathered at Serpent Mound for the solstice candle lighting. Photos courtesy of Jeff Wilson and Bill Jordan.

Figure 3. View of the Adena conical burial mound at winter solstice sunrise. Photo courtesy of Thomas T. Johnson.
The conical burial mound was excavated in the late 1800s by Frederic W. Putnam of Harvard University. The mound was found to contain several burials. The central burial was an adult male with his head oriented to the east. Among the many items found in the mound were flint and ground stone implements, pottery sherds, pieces of fresh water clam shell,  burned bone, and a copper plate. Based on diagnostic findings the conical burial mound is attributed to the so-called Adena people.

The conical burial mound is an integral part of the Serpent Mound earthwork complex.

The burial mound is directly associated with the serpent effigy and the winter solstice sunset in the following way.

First, with reference to Figure 4 below, the LiDAR-measured distance (line A-B) between the apex of the oval embankment and center of the conical burial mound is 1,178 feet +/- ca. 2 ft. The significance of the 1,178-foot length is that it is found at other Moundbuilder earthwork sites. The diameters of the Newark Great Circle and Shriver Circle near Mound City, for example, are each 1,178 feet in length.

Second, the orthogonal (or perpendicular) of the 1,178-foot line is oriented to the winter solstice sunset to within two-tenths of one degree. (The 237.2-degree azimuth value takes into account distant horizon elevation, refraction, lower limb tangency, latitude, and 0 A.D. date +/- 200 years.)

Figure 4. LiDAR image of the Serpent Mound park.

Notably, the 1,178-foot length is derived from the Hopewell Measurement Unit (otherwise known as the HMU) of 1,054 feet. The 1,054-foot length (as well as greater and lesser multiples of that length) is found in many Adena-Hopewell earthworks including the Newark Octagon and Observatory Circle, Mound City, Hopeton, Baum, Shriver, and others. 

Figure 5 shows examples of the 1,054-foot length and how the 1,178-foot length is related to the HMU.
Fig. 5. LiDAR images of the Newark Octagon and Observatory Circle and Newark Great Circle showing how the HMU is incorporated and how the 1,178-foot length is derived.

Given the above, I believe several conclusions can be reasonably drawn: 

1) the serpent effigy, conical burial mound, and other ancient features in the park were likely intended by the Moundbuilders to comprise an integrated site complex. 

If this is true then, physical and visual barriers that divide the area - such as the one currently being planted and grown at Serpent Mound are inappropriate.

2) the linear and astronomic relationships between the serpent effigy and conical burial mound suggest that these relationships were not only intentional, but that their construction was likely contemporaneous, or very nearly so. Certainly that is the simplest explanation. If that was the case, then this provides further support for the recent finding that Serpent Mound was built during the Early Woodland period (see blog page elsewhere on this website concerning the new radiocarbon dates). 

3) the alignment data shown here suggest that winter solstice observations were part of the Ancient Ones understandings relative to Serpent Mound. Moreover and based on the relationship of the conical mound to the winter solstice, it seems likely that burial ceremonies, ancestor memorial events, world renewal ceremonies, and other activities may have been timed to celestial events - to include the winter solstice. If that was the case, then it is entirely fitting and proper that solstice celebrations should continue at Serpent Mound in recognition and in honor of those who built this world-class effigy. 

The Serpent Mound winter solstice candle lighting event has been a local tradition for a decade. Many people contribute to its success. Mostly, however, the event is the result of the hard work and dedication donated by members of the Friends of Serpent Mound. FOSM is comprised of individuals, organizations, and businesses dedicated to the preservation, protection, and promotion of Serpent Mound. For more information see the Friends of Serpent Mound website ( and Facebook page (http://www.facebook/groups/friendsofserpentmound/).