What is the DMZ? Map and pictures show the demilitarized zone Travis King tried to cross into North Korea

This week U.S. soldier Travis King crossed the Demilitarized Zone, often call the DMZ, which separates South Korea and North Korea. King went into North Korea "willfully and without authorization" and is believed to be in the custody of North Korean forces. What is the DMZ and what does it look like?

The DMZ is a 148-mile-long strip that incorporates territory from both North and South Korea. It is about 35 miles from South Korea's capital, Seoul, and runs along the 38th parallel, the line that divides the two countries, along which much of the Korean War occurred.