Istanbul has the worst traffic congestion in Europe, which beats out even the terrible backups in Los Angeles by more than 50 percent. The worst of it, in both cities, occurs in the early evening as everyone is returning home from work. So, if you're vacationing in either destination, it might be best to catch a long dinner during those hours to avoid wasting time in a rental car or cab.

If you thought your commute was bad, stop complaining, because it could be worse.

Unless you live in Turkey.

GPS navigation system maker Tom Tom has released its annual lists of the most-congested cities in North America and Europe.

Using real-world data collected from its users, the company has developed a congestion index which compares peak to non-peak travel times and calculates the percentage difference.

Topping the list among U.S. cities is Los Angeles with a 34 percent overall rating that jumps to 74 percent during the peak of the evening commute.

Read More on embarq.org