Holiday travelers line up on Thanksgiving eve for a security screening before boarding their flights in Washington, DC. / PAUL J. RICHARDS | AFP | Getty Images

Video: Simon Calder explains why the Thanksgiving holiday is the ultimate nightmare for the US traveller

Thanksgiving, celebrated on the fourth Thursday in November is a time of great celebration for Americans as they give thanks for the safe arrival of the pilgrim fathers to Plymouth, Massachussetts.

Of course, many now give thanks for the fact that the majority of the population get a four-day weekend and many look ahead to Black Friday - the day when shoppers give thanks for bargains.

However, with so much of the population travelling across the country to return home and spend time with family, the five-day period between Wednesday and Sunday becomes the most expensive and stressful time for Americans to travel.

This period has the highest fares in the U.S. travel calendar - much worse than just before Christmas or at the peak of the summer season. The Wednesday before Thanksgiving and the Sunday afterwards, when everyone returns home before the start of the working week, are the days when travel fares reach their highest.

You can actually get very good travel deals on Thanksgiving Thursday - but many Americans prefer not to travel on the actual holiday.

None of this has been helped by the recent weather on the East Coast.

More than 200 flights were canceled at airports in the northeast due to snow forecasts. Thousands of flight delays are now expected as snow moves into the Boston-Washington, D.C. corridor. says approximately 180 flights were canceled Wednesday morning in Newark, New Jersey, and at New York's LaGuardia, Kennedy and White Plains airports.

More than a dozen flights were canceled at Philadelphia and Boston.

According to the US Department of Transportation, the number of long-distance trips taken by Americans over the holiday period increase by 54 percent. Over the Christmas and New Year period, the increase is under half of that at 23 percent.

For those traveling by air, bus or rail, the department says that Wednesday's volumes are higher than Thursday's.

The American Automobile Association projects that 46.3 million people will journey 50 miles or more from their homes during the Thanksgiving weekend.

That's important to remember: not everyone is flying or travelling by train or bus. As the department's website notes, "While crowded airports and bus and train stations receive heavy media attention, nine out of 10 travelers use personal vehicles."