The Whistler owes the name to the sound from countless birds that lay on its branches. Planted in 1783 in Águas de Moura, this cork oak has already been stripped more than twenty times. In addition to the contribution to the cork industry, it has huge relevance for ecosystem services and fighting climate change. With 234 years, the Whistler has been classified as "Tree of Public Interest" since 1988 and is registered in the Guinness Book of Records: "the largest cork oak in the world".