The Whistler Tree is a more than 235 years old natural wonder in old cork oak from Águas de Moura, Palmela, Portugal. This cork tree is about 16.3 m (53 ft) tall and has a diameter of 14 ft.
In 2018, The Whistler Tree is voted European Tree of the year. It is also known as the monumental Cork Oak (Sobreiro Monumental). A cork is made from the bark of a specific species of an oak tree.
 
In 1988, this cork tree has been classified for the Public Interest and registered in the Guinness Book of Records as one of the largest cork oak trees in the world. The plantation date is 1783 and after that, the tree has been harvested more than 20 times. The Whistler Tree yielded more than 1,200 kg of cork producing over 100,000 cork stoppers in 1991.
A single cork tree yields 100 pounds of bark, an adequate amount of cork for about 4,000 bottles. The extraordinary cork-producing ability makes this tree so special as the average cork tree would yield in its entire life. Naturally, a cork tree is harvested for the first time when it reaches the age of 25.


