The Origins of Port
Port Wine, originally referred to as "Red Portugal," now called "porto" or just "port," is brandy-fortified wine made from the grapes of the Douro Valley in northern Portugal. The region itself consists of an officially demarcated area of approximately 1,000 square miles, and it stretches from about 60 miles east of the city of Porto along the Douro River to the border of Spain. Most Port wines are red, but a white variety is also available. Port, which gets its name from Porto, the second largest city in Portugal, is typically served after dinner as a dessert wine.

How Port is Made
Harvest is in late September and early October. There are many different local grape varieties of which about a dozen are used for Port. The grapes are harvested by the "roga", a traditional group of harvesters from a closely-knit community, that by tradition returns to the same "quinta" or farm every year. They work from sunrise to sunset until all the grapes are harvested.
The grapes are then crushed and partially stalked. Fermentation begins and continues for between 36 and 48 hours.Pure grape brandy is then added to the wine to stop fermentation before the yeasts consume all of the grape sugar, thus a sweeter wine (with a higher alcohol content -- at least 33 proof) is produced. The young Port is allowed to settle for a few months in vats or casks made of oak or mahogany before being taken to the maturing lodges in VilaNova de Gaia near Porto. Here the Port wines are left to mature anywhere from 3 to 50 years.

The Vintage
The type of aging process (i.e. wood vs. bottle aging) and the age of the Port itself determines the character and flavor of the wine.

Wood-aged Ports
Ruby,Tawny,White: These ports are blended to produce wines of fine balance     and flavor. Usually bottled when three years old.

Vintage Character: These have a full, rich flavor, color and smoothness and     are bottled when 4 to 5 years old.

The Old Tawnies: These ports are aged 10 to 40 years in oak casks. They     eventually take on the classic amber shade which gives them their name.

Bottle-aged Ports
Crusted: Ports of different years are blended together and bottled,      unfiltered, when young. In time the port will throw a deposit or crust.

Single Quinta: These are a product of a single estate. They are bottled after 2     years and allowed to mature in the bottle before being sold.

Vintage: This port is an outstanding wine of an outstanding year. The wine is     aged for about 2 years in wood before being bottled unfiltered.