The emergency sirens blared across the city this afternoon for the monthly readiness drill. Most people ignore them, and the rest wish they could ignore them, particularly the drivers stuck in the photo here.
It goes like this: the sirens go off for a couple minutes, during which people in tan jackets walk out into the street and make all the traffic stop. Then some guy in a truck rolls up and down the street a few times, yelling on a bullhorn, making sure that if any military (?) vehicles were to come they could pass through quickly. Overhead the rare sound of miltary jets is breifly heard (an uncommon sound in Seoul, but a nuisance in other parts of the country). After about 20 minutes the sirens sound again for a minute, the tan jackets disappear, and traffic resumes to normal. Well, normal is subjective. It usually takes a couple hours or so for the consequential traffic jam to disperse--just in time for the evening commute.

That was annoying yesturday....my kindy kids always panic when it happens..and I have to explain to them that it is not a fire..because the sirens sound like our fire alarm. Glad I wasn't stuck in traffic though.
How often do they have defense readiness drill?
I believe it's once a month.