Fort Ancient is designed mainly with earthen walls, gateways, and ponds, though there are a variety of mounds as well. Archaeologist Robert Connolly explains their roles in the design:

Very few of the mounds at Fort Ancient contained burials. They may have been used for signal fires as in the North Fort: Moorehead in the 1890’s reported that these were basically large piles of limestone that were very heavily burnt. We also know that mounds marked the entryways of primary gateways into the enclosure, and really were sort of a signaling device: people would see the large Twin Mounds (for example) and say, ‘Oh that’s the appropriate place to enter the earthwork complex.’ So the function of the mounds here at Fort Ancient was much beyond that of simply burying the deceased kin.