Last year I happened to be driving by the Deer Park winery tasting room in Escondido with G.A. and we decided to stop in to waste a little time. They were tasting thier "library" zins. I don't recall exactly what vintages we tasted, but some of them were like 15 years old! It was kind of a morbid curiosity that drove us to sample the stuff. If memory serves me correctly they were WELL past prime and kinda rancid. I had never tasted an old zin. and it was a different experience all together.