93 Points - Revista Adega. The Fonseca 20 Year Old Tawny Port is a traditional blend of grapes including Tinta Roriz, Tinta Cao, Touriga Nacional, and Tinta Francesca. Under the expert guidance of David Guimaraens, a sixth-generation winemaker, nothing is left to chance. Grapes are gathered from the best vineyards in the Cima Corgo and Douro Superior regions and are made in the traditional way with fortification with grape spirit halting the fermentation to leave some residual sugar in the wine. Starting life as a lip-staining purple, the wine is placed into small oak casks of around 630 litres, from which it emerges two decades later as russet red, mellow, complex and utterly delicious.