This work is situated in Franklin county, Tennessee, at the junction of the east and west branches of Duck river, and near the main road from Nashville to Winchester.
"It includes an area of about thirty-two acres. The walls are composed of stones of various sizes, collected from the surface of the surrounding country, and rudely thrown together; there is no appearance of their having been united by cement, nor do they exhibit any marks of the hammer. The wall on the south is covered with a layer of earth from one to two feet deep, and is about sixteen feet in thickness at the base, about five feet at the top, and from eight to ten feet high.
"At the northern extremity, near the front wall, are two conical mounds of stone, designated by M, M, in the plan. Each of these mounds is about six feet high, and ten feet in diameter at the base; originally they may have been of somewhat greater altitude, and being on the exterior of the wall, may have been intended as watch towers. In the rear of the mounds is the northern wall, extending to a high bank on either branch of Duck river, and opposite to a waterfall on each, of ten or twelve feet in height. In the northern wall is an entrance or gateway, and in the rear of the gateway are what appear to be the remains of two stone buildings (exaggerated in the plan), one about sixteen feet square, the other about ten feet; the stones are rough and unhewn. Stretching south, the walls are continued on both sides until they reach the points a a, at a bold limestone bluff, which forms a good natural defence. South of the bluff the walls are continued of the same height and thickness, until they reach the angles of the wall fronting the south which wall also extends from the bank of one river to the other, and has a gateway nearly opposite to that in the northern wall. At the points a a, it is supposed by many who have examined this work, there were formerly excavated passages leading to each branch of Duck river, with steps cut in the rock. There does not, however, appear to be sufficient evidence to sustain this conclusion. The ascent or descent is not very difficult; the steps appear to be formed by the projection of the rock strata; and it was no doubt by these passages that the occupants of the work gained access to the river, and were supplied with water.
"Near the base of the wall on the south side is a ditch, from sixteen to twenty feet wide, and six or eight deep. A short distance farther from the southern wall is another and much more extensive ditch or excavation. In some places it is seventy or eighty feet wide, and from twenty-five to thirty feet deep. The earth from these ditches was probably removed to cover the walls of the fort, or employed in the erection of the neighboring mounds, while the ditches themselves constituted an additional means of defence.
"About three quarters of a mile north of this work is a mound of an oblong form, about twenty-five feet high, one hundred feet long, and twenty broad. On the north-west, about half a mile distant, is another mound of similar form, twenty feet high, eighty long, and sixty wide. These mounds are constructed with the same regularity that distinguishes all the other works of similar character. On both these mounds, trees are growing as large as any in the surrounding forests.
"This work differs in its form, and in the material used in its construction, from all others in the vicinity; but it does not exhibit greater evidence of skill. The difference in form was probably owing to its location; it having evidently been made to conform in all respects to the nature of the ground. Stones were employed because they could be readily procured. Although the hammer had nothing to do with the preparation of the materials, it was nevertheless a work of great labor, and the place of location was selected with a military eye."