Our oldest Olive tree

In one of our Groves, in Monemvasia at  GR-230 70 Greece, with 36°45'10.0"N 23°00'41.2"E we have the oldest Olive tree of our Groves. We don’t know the exact age of the tree. (the only way to find out the age is to cut the tree and count the yearly developing rings, but of course we would never cut that nature’s monument). However the tree is estimated (based on its diameter) to be 1200-1500 years old.
We call it "GREA" which in ancient Greek means the old lady, or the grandmother. Grea has been an eyewitness of the local history. The area experienced endless wars, invasions and change of rules in the regions. From Spartans to Romans then to mighty Byzantine Empire, later to Venezians and the Ottoman Empire and after the Greek revolution to several owners.
Our Grea is not a very productive tree, but it still manages to produce about 150 kilos of olives and 35 kilos of fine extra virgin olive oil with a very low acidity of 0.2-0.3% per year.