Bartek (Polish: Bartholomew) is an ancient oak tree in Poland. It grows in Zagnańsk near Kielce in the Świętokrzyskie Mountains. Its age, previously estimated at up to 1200 years, has recently been established to be 650–670 years, with a corer used to extract a sample for a ring count. An accurate count is impossible, as Bartek's interior has hollowed with age. There are several older trees in Poland, both oaks and yews (some over 1000 years old), yet none of them has matched Bartek's fame.