modern research (2004) into the history and archaeology of derby has provided evidence that the vikings and anglo-saxons would have co-existed, occupying two areas of land surrounded by water. the "anglo-saxon chronicle" (c. 900) says that "derby is divided by water". these areas of land were known as "norþworþig" ("northworthy", = "north enclosure") and deoraby, and were at the "irongate" (north) side of derby.