Little is known about the city of Cölln, across the Spree River from Berlin, Germany, but that may change with the discovery of medieval buildings and nearly 4,000 skeletons. Cölln, the older of the two cities, declined and was incorporated into Berlin.
Researchers understand little about how the two cities came to exist equally in the same area, creating rivalries. A fire in the 14th century destroyed many historic documents pertaining to Cölln, and plague ravished both cities.
In addition to the remains, archaeologists have unearthed "the old foundations of St. Peter's Church, the remains of Cölln's town hall and a Latin school that burnt down in 1730."