Port is made in the Cima Corgo, Baixo Corgo and Douro Superior districts of the Douro Valley in the north of Portugal. The summers are hot and dry and the climate becomes more continental as you move further east towards the upper Douro Valley. Here temperatures often exceed 40 degrees. The Douro Valley has steep hillsides with terraces, which is not only aesthetically pleasing but is also extremely useful for making quality wine. The schist soils aid in drainage and have become very important to port production, so much so that much of the Douro table wines have been relegated to granite soils. The six main grape varieties used for port production are Touriga Nacional, Tinta Cão, Tinta Roriz (Tempranillo), Tinta Barroca, Touriga Francesa and Tinta Amarela. There are another 42 grape varieties that are permitted but these six are considered to be the noblest ones, each adding something different to the blend. After the harvest the grapes are trodden, often by foot but more often by machines, in giant lagars (troughs). Port is a fortified wine so during fermentation ‘brandy' (not actually brandy but a grape-distilled spirit) is added to increase thealcoholic strength to around 17-19 % abv. This leaves a sweet, red fortified wine with lots of vibrant fruit. There are many different types of Port from the Basic Ruby Ports, through to Tawny Ports and LBVs, to probably the most famous of all Vintage Port that can take 20 years to reach its peak. When mature, Vintage Port is a unique tasting experience with warm, concentrated spicy-fruit flavours and a superb length that just goes on and on.