Eketorp exterior wall with sheep grazing The long houses. The water well inside the fort, no doubt a strong reason for its location

The indigenous peoples of the Iron Age constructed the original fortification about 400 AD, a period known to have engendered contact between Öland natives with Romans and other Europeans. The ringfort in that era is thought to have been a gathering place for religious ceremonies and also a place of refuge for the local agricultural community when an outside enemy appeared. The circular design was believed to be chosen because the terrain is so level that attack from any side was equally likely. The original diameter of this circular stone fortification was about 57 metres (187 ft). In the next century the stone was moved outward to construct a new circular structure of about 80 metres (260 ft) in diameter.[1] At this juncture there were known to be about fifty individual cells or small structures within the fort as a whole. Some of these cells were in the center of the fortified ring, and some were actually built into the wall itself.

In the mid 600s AD, the ringfort was mysteriously abandoned, and it remained unused until the early 11th century. This 11th century work generally built upon the earlier fort, except that stone interior cells were replaced with timber structures, and a second outer defensive wall was erected.