As one can see from the “city map” (Figure 3), the town was divided into several areas. The main area in the middle of town was dominated by a semicircular or partially octagonal enclosure. The enclosure was produced by six artificial, earthen embankments which formed concentric arcs. Extra ridges were outlined in the western sector, and the outer ridge terminated before reaching the south sector. The ridges were between 50 and 150 feet apart and about the same in width. They were 4 to 6 feet tall. Between them were low areas, or swales, apparently where much of the construction dirt had been removed. From one end of the outer arc to the other was 3950 feet, or nearly three-quarters of a mile. Opposite ends of the interior or smallest embankment were 1950 feet apart. All of the ridges terminated at the edge of a bluff, which dropped steeply some 20 feet below to a stream which paralleled the entire eastern side of the earthwork. Formerly, archaeologists suspected that the ridges formed a complete circle or octagon and that the Arkansas River, which once flowed by the site, had eaten away the eastern side. Recent geological information and studies of activity patterns on the site, patterns that include both occupational and architectural tasks, now show that the enclosure was always semicircular. The bluff that marks the eastern edge of the site today and which seems to have cut into the earthwork was formed thousands of years before building ever started. In fact, the bluff edge has probably retreated very little since the time of earthwork construction. The ridges were divided into five sectors by four aisles, or corridors. These openings range from 35 to 160 feet in width. They did not converge at a single point in the middle of the enclosure; neither did they divide the encircling embankments into equal-size areas. The middle of the enclosure, or plaza, was relatively flat and covered an area of about 37 acres. At the eastern edge lay an oval mound (Bluff Mound). Whether it was built during Poverty Point times or during the Civil War, as claimed by some, is not certain. Outside the central area were other earthworks (Figure 4). These included mounds and other embankments, as well as depressions. Physically connected to the outermost arc in the western sector was a huge mound (Mound A). The mound had an unusual shape which reminded some experts of a bird. It stood over 70 feet high and measured 640 feet along the “wing” and 710 feet from “head to tail.” The flattened, or so-called “tail,” section of the monster structure was actually built in a pit some 12 or more feet deep. Another similar but slightly smaller mound (Motley Mound) was built 1.5 miles north of the central embankments. Because it had only a lobe where the “bird’s tail” should have been, it was believed to be unfinished (Ford and Webb 1956:18).