One of my favourite grape varieties purely because the name means ‘red dog’! It is very low yielding and produces concentrated, spicy grapes. Its low yielding nature meant that the variety almost went extinct after phylloxera epidemic when growers favoured more productive varieties.
Cooler sites actually suit the variety as it brings out its more elegant, floral flavours. It is very late ripening and producers will often let the grapes ripen into November before picking.
Outside of the Douro but still in Portugal, it is grown in Dão and is also being experimented with in California.