For The Love Of Port

As in the topic title, when were the Tawnies with indication of age first produced?

Before that, were most of Tawnies still done by blending different harvests?

Hello all, first time poster My name is Romão, I was born and raised around the Porto area and as of the last few months I've being working as a Tour Guide at the Calém Lodges. I don't have a vast experience as a Port Wine drinker per se, although I'm greatly interested in the history of the whole t...