We have defined a region extending at least 2,000 km, from central Yugoslavia and NW Greece to eastern Turkey and south to Cyprus, within which the annual growth rings of pines and oaks are so similar that they may be compared for hundreds of years at a time. Within this region, we have established a North Greek Oak Master Chronology extending 864 years back from 1979 to 1116 A.C. linking oak samples from 33 standing churches, mosques, and houses in absolute chronological relation to one another and to sequences from forest trees. It also synchronizes with our 700-year long sequences from pines in both Greece and Trukey. For a given oak treee used as structural timber we are now able to determine the felling year at any time since the middle of the 12th century by comparing its ring patterns to the master sequence and can thereby offer precise dates for hitherto undated standing or excavated buildings. We are continuing to add to the list of absolutely dated sites while at the same time attempting to extend the length and geographical scope of the absolute master chronology. Ultimately, it may be possible to link our absolute sequence to the floating 806-year Iron Age tree-ring sequence from Gordion and the 364-year Middle Bronze Age sequence from Acemhüyük.