Poverty Point Culture - Earthworks

Earthworks

Although the earthworks at Poverty Point are not the oldest in the United States, (the earthworks at Watson Brake were built about 1900 years earlier) they are notable as the oldest earthworks of this size in the Western Hemisphere. In the center of the site is a plaza, a constructed and leveled, flat, open area covering about 15 hectares or 37 acres (150,000 m2). Archeologists believe the plaza was the site of public ceremonies, rituals, dances, games and other major community activities.

The site has six concentric earthworks separated by ditches, or swales, where dirt was removed to build the ridges. The ends of the outermost ridge are 1,204 metres (3,950 ft) apart, which is nearly 3/4 of a mile. The ends of the interior embankment are 594 metres (1,949 ft) apart. If the ridges were straightened and laid end to end, they would comprise an embankment of 12 kilometres (7.5 mi) long. Originally, the ridges stood 4 feet (1.2 m) to 6 feet (1.8 m) high and 140 feet (43 m) to 200 feet (61 m) apart. Many years of plowing have reduced some to only 1 foot (0.30 m) in height. Archeologists believe that the homes of 500 to 1,000 inhabitants were located on these ridges.

This was the largest settlement at that time in North America. The site also had a 50 feet (15 m) high, 500 feet (150 m) long earthen pyramid, which was aligned east to west. A large bird effigy mound, measuring 70 feet (21 m) high and 640 feet (200 m) across, is also located on the Poverty Point site.

On the western side of the plaza, archeologists have found some unusually deep pits. One explanation is these holes once held huge wooden posts, which served as calendar markers. Using the sun’s shadows, the inhabitants could have predicted the changing of the seasons. This great building project demanded a sustained investment of human labor, the organized skill and the cultural will to sustain the effort over many centuries. One authority calculated that it would take more than 1,236,007 cubic feet (34,999.8 m3) of basket-loaded soil to complete the earthworks. That would mean 1,350 adults laboring 70 days a year for three years.