Bangkok Half-Marathon Accidentally Adds 4 Miles to Route

An error by race organizers has made Bangkok home to the world's longest half-marathon.

Instead of the typical 21-kilometer (13-mile) run through the steamy Thai capital, the Standard Chartered Bangkok Marathon on Sunday accidentally extended its annual half-marathon to nearly 28 kilometers (17 miles).

The bonus came as a surprise to runners, who unleashed a tirade of complaints on social media after the event.

The race organizers, the Jogging Association of Thailand and private promoter Amazing Field, had no comment Monday and have not said anything publicly about the error.

But the Athletic Association of Thailand, which oversees athletics events in the country, called it a "technical error" that was "an unfortunate accident."