The oldest and most productive cork oak in the world is the Whistler Tree, in Águas de Moura, in the Alentejo region (south of Portugal). The cork oak was planted in 1783, stands over 14 metres tall and the diameter of its trunk is 4.15 metres. In 2018, the Whistler Tree, representing Portugal, was voted European Tree of the Year. Its name comes from the noise made by the numerous songbirds that shelter among its branches. Since 1820, it has been harvested more than 20 times. Its 1991 harvest produced 1200 kg of cork, more than most cork oaks yield in a lifetime. This single harvest produced more than 100,000 cork stoppers.

(From www.amorim.com)