Archaeologists in Germany say they've used tree-ring data to identify four ancient water wells as some of the world's oldest timber constructions.

A research team led by the University of Freiburg said the wells excavated at settlements of the first Central European agricultural civilization in the Greater Leipzig region are the oldest known timber constructions in the world, dating to between 5,600 to 4,900 B.C.

The four early Neolithic wells were constructed from oak wood and contained wooden artifacts, bark vessels, fiber cords and an array of richly decorated ceramic vessels, a Freiburg release reported.

Using dendrochronology -- a count of tree rings -- the scientists were able to determine the exact years the trees were felled and therefore the approximate date at which the wells were constructed.

The wood comes from massive old oak trees felled by early Neolithic farmers with stone adzes from 5,206 to 5,098 B.C., and the well-preserved tool marks and timber joints in the wells testify to unexpectedly sophisticated timber construction techniques, they said.