Seoul is experiencing a mass exodus of millennials who can no longer afford the high cost of living in one of the world's most expensive cities. There are still many people in their 20s moving to the capital to study and work, but the exodus has begun among people who have jobs and are raising children.

According to figures released by Statistics Korea last year, the number of 30-somethings leaving Seoul was 42,521 higher than of those moving to the city, accounting for a third of its net population loss. They were followed by those in their 40s (26,459) and those in their 50s (24,311). Since 2010, Seoul citizens in their 30s dwindled from 1.74 million to 1.54 million last year.

Refugees normally end up in the anodyne satellite cities around the capital. Gyeonggi Province surrounding the capital saw an inflow of 49,575 people in their 30s last year, the biggest increase in any age group.

A staffer at Statistics Korea said, "Young residents tend to move out of Seoul due to high housing prices and changes in their lives such as marriage and employment."

