The South Korean recruits working as border guards
16 January 2014 Last updated at 16:04 GMT
In South Korea, military service is compulsory for all young men once they turn 18.
The hostile relationship between North and South Korea means new recruits are on constant alert.
Kim Young Hoon, 20, a private in the South Korean Army, talks about what it is like to face the ever present danger from North Korea.