The Southwold Prehistoric Earthworks was recognized as a National Historic Site in 1923 and is now under the care of Parks Canada. The earthworks are the only visible remains of a native village inhabited around AD 1500 by the Attiwondaronk Nation. The 2.2 hectare (5.5 acre) site is situated in an area of fertile farmland, once the western portion of the Attiwondaronk settlement which stretched from Kent County to the Niagara Peninsula.

The double wall of earthworks constitutes one of the most remarkable features of the village. The outer earthworks surrounded the 2 acre oval-shaped village except for the openings where a stream entered into and exited from the enclosure. The inner earthworks displayed a similar gap on the southwest to west perimeter of the site, where the stream cut in to the village. Scientific evidence indicates that the outer palisade was constructed first. Posts, or tree trunks, pointed on the bottom, 4 to 5 metres in height, were driven into the ground. Earth was then scraped from both sides to support the structure leaving the present trench. The inner palisade consisted of a double row of posts, soil was again taken from around the base and put against the posts, braces were also used at intervals for additional support.