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Four Things to Know About Traffic Congestion

Professional drivers know all sorts of secrets for getting places faster and avoiding traffic jams. To understand what they’re up against, check out Groupon’s look at traffic delays.

1. It doesn’t take much to start a traffic jam. Even on a straight highway with no accidents or construction, a single driver tapping the brake can create a stop-and-go wave. When vehicles enter the rear of a suddenly slowed traffic flow faster than cars at the front can accelerate back to regular speed, congestion ensues. These “phantom jams” have been documented stretching as far back as 50 miles and, once traffic reporters spread the word, can attract dozens of boombox-bearing ghosts.

2. On the flip side, you can do your part to prevent them. Through computer modeling of this scenario, MIT computer scientist Berthold Horn has found that phantom jams can be significantly reduced if drivers maintain an equal distance between the car in front of them and the car behind.

3. In the world’s most congested areas, at least you can enjoy the view. Traffic research firm Inrix releases an annual report on the worst spots for delays, and in 2014, tourist destinations Milan and Honolulu took top honors. Depending on the season, the average Honolulan loses three to five hours a month to jams. Why? One major factor is simply that it’s on an island, so there’s limited room for road systems to expand and relieve the pressure.

4. Don’t believe anyone who says Thanksgiving is the busiest traffic day of the year. There are typically five or more busier days during the summer, often Fridays when people are driving to weekend destinations to enjoy the warm weather or escape the ice-cream truck’s infernal tune.