The Douro River runs through the middle of Portugal. It cuts west to east from the Spanish border until it spills into the Atlantic Ocean. Steep rugged cliffs, rising up four to five hundred metres, flank the route of the river. The heat in summer on those cliffs climbs to 120 degrees or more. There is no shade. The soil is baked dry. To walk upon it is to sink into layers of dust. It is a land not fit for people or for many other living things. And yet within this inhospitable terrain, not navigable by car or tractor or any other motorized accessory, lies the heart of the port wine industry and a grape so hardy its roots can tunnel up to 30 metres deep into the rocky soil in search of water.

The port grape, scrappy and thick skinned, essential to holding what little water it can find in this region, is an apt metaphor for the story of port itself. It is, in the world of wine, the ugly stepchild, or better yet the cranky old uncle. English most likely and laid lame by gout. He sits by the fire holding a leg of mutton in one hand and a glass of port in the other. He is always alone except for the decaying wolfhound lying at his feet. This is unfortunately the image most often conjured up when one thinks of the standard port drinker. It is an image Dan Carbon has worked hard to dispel.

Dan Carbon was, until recently, the head of marketing for the Symington Group, the largest producer of premium port wines in the world. Their brands include Graham’s, Warre’s and Dow’s among other port labels.

“Port has probably two huge challenges,” Mr. Carbon says. “Consumer misperception and the moment of consumption.”

The confusion over the moment of consumption, or, in other words, when you toss back a glass of the stuff, is rather easy to demystify. “I think it is following any meal where you are socializing with friends,” Mr. Carbon says. So much for the lonely old guy sitting by the fire. Although, by his own admission, Mr. Carbon does also enjoy a quiet contemplative glass too.

Unpacking consumer misperception is a more complicated task requiring a bit of port education. Next weekend on Saturday, Oct. 16 at 11 a.m., as part of the two-day food and wine festival taking place at restaurants all around Martha’s Vineyard, Mr. Carbon will be giving a port talk and tasting. His tasting is, in his words, “an ideal opportunity to vet out what you like and what you don’t like.”

But for now a bit of a port primer to whet the appetite.

Once upon a time, 1703 to be exact, the British and French were not getting along. As a result Britain banned the import of all French wine. Man cannot live on warm pub beer alone, however, and so the country began importing wine from Portugal. These were the days when cargo was transported primarily by ship and the long, hot trade routes often caused the wine to spoil. Out of necessity, the Portuguese began adding brandy to the crushed grapes in order to kill the yeast and stop the fermentation process, thus creating a much more stable product to ship. The result was port, a spirit that is essentially a mix of three parts wine to one part brandy.

Okay, history is nice but what to do if wandering the aisles of the local liquor store. In other words, how do you know what to choose today?

“There are two main branches of port wine,” Mr. Carbon explains. “Port that’s been bottle-aged and port that’s been wood-aged. The starting point is the same but the end result is very different.

“When you wood age a port wine you tend to take away the vibrant, full, bright fruit flavors and instead you start to layer in flavors of honey and caramel and spices. If you took that exact same port wine and put it into a bottle the oxidation is minimal or nonexistent. The wine that is in the bottle will maintain its color and its fruit.”

He suggests starting out with a bottle of each:

“A 10-year-old tawny port is a great introduction to the world of port that’s been wood-aged. Then buy a bottle of reserve or LBV (late bottle vintage).” Mr. Carbon feels that Graham’s Six Grapes is a good example of an introductory LBV, or bottle-aged, port and that Graham’s or Dow’s or his competitor Taylor’s all make wonderful tawny, wood-aged, ports.

“The next step would be to go up the ladder in quality. Most people would say a 20 or 30-year-old port is the pinnacle of wood-aged port. If you preferred the LBV, you might buy a Single Quinta or Vintage Port. But now they are not going to be cheap anymore.”

It can be a slippery slope, this journey into fine ports. But the beauty is that because the fermentation process has been stopped during the production, an opened bottle of port lasts a lot longer than wine. There is no need to dig one of those air pumpers out of the drawer to salvage a few more days of quality drinking. An open bottle of port lasts up to a month. But the problems of port, not its taste which is delicious, but the public misconception or downright dismissal in favor of more known entities, a bottle of red wine, a six pack of beer, are both its Achilles heel and its shining arrow. Take Mr. Carbon’s own journey. Were it not for the mystery of port he may never have altered his life’s course.

Mr. Carbon is a native of the Vineyard. After graduation, he attended the University of Massachusetts, then moved to New York city to work in finance. A few years later he relocated to San Francisco where he worked at a start-up company doing in-store advertising. Soon this small company went public and Mr. Carbon used this as a golden opportunity to plan a life change.

He had recently begun dating another Vineyarder, Shannon Gregory. They had known each other growing up on the Island but not very well. After bumping into each other at the New Orleans Jazz Festival, they began dating long distance. Mr. Carbon still lived in San Francisco while Ms. Gregory had put down roots in New Orleans. But she was also ready for a life change.

“Shannon was just great at helping me think about a life with no constraints. What then would you do and what regrets would you have? Well, I’d regret I didn’t travel enough internationally. I’d regret I didn’t learn a language. So she said, how can we do all those things? Let’s figure it out.”

Mr. Carbon had just begun to fall in love with port, both the taste and the history. His grandfather had emigrated from the Azores and so he felt a connection to Portugal and its culture. “I ended up getting very passionate about it (port) and said I’m going to enter the port trade. Which was crazy.”

And so at the age of 34 Mr. Carbon and Ms. Gregory embarked for Portugal. Mr. Carbon didn’t have a job or much in the way of connections. But he did have the Portuguese people and a culture of embracing even the nuttiest interloper.

“A good example of the Portuguese culture is the people just take you in. If you ask someone for directions on a rainy day in downtown Porto they take you to where you are going.”

And in terms of his specific journey?

“They said, wow you are doing something completely foolish. How can we help you?”

Eventually, he found a job with the Symington Group and rose up through the ranks. But life, like a bottle of port, is a fluid organism. Mr. Carbon and Ms. Gregory married. They had two children.

“I probably had one of the best jobs in the world. But we had two children and the (Portuguese) culture is wonderful but it’s not my culture. So as much as we loved it we felt alienated and we missed family. We missed seeing our kids seeing our family.”

In March they moved home to the Vineyard. Ms. Gregory’s father owns Educomp in downtown Vineyard Haven.

“My background is working on computer networks. He (owner and father-in-law Pat Gregory) is stepping out of the business and I’m stepping in. I feel like it really works well. We moved back for family,” Mr. Carbon says.

The story of port and the story of Dan Carbon are just two of many stories available next weekend at the food and wine festival. The event will feature two full days of drinking and eating and learning about drinking and eating. Always the best atmosphere to hear and tell stories.

The festival begins on Friday, Oct. 15 at 4:30 p.m. with a free opening reception at the Eisenhauer Gallery in Edgartown. At 7 p.m. the night continues with an event at the Boathouse Field Club in Katama, featuring the wines of Joseph Carr. On Saturday the festivities begin at 11 a.m. with a Sake 101 class. The rest of the day and evening include cooking demonstrations and dinners created by world renowned chefs, wine tastings and lectures and much, much more.

For a complete listing of events visit mvfoodandwine.com.

Meanwhile, sit back with some friends and enjoy a glass of port. And there’s no need to be confused. Wood-aged or LBV, there’s something to satisfy every taste.