Walled City of Pyongyang
The Walled City of Pyongyang was built in the period between 552 and 586 after Koguryo moved its capital to Pyongyang in 427.
The walls were erected along the areas with plains and low hills and they were favourable for defence as they had the Taedong and Pothong rivers on the three sides.
The walls were 16km in circumference and the total length of the walls plus sectoral walls in the walled city consisted of the inner, central, outer and northern walls. In the central wall there were central government offices. In the walls there were gates, secret gates and water gates.
Taedong, Chilsong, Pothong, Jongum and Hyonmu gates still remain intact, preserving their old looks. In front of the wall gates leading the outside, breast walls with defence facilities were built up. There were 210 508 households in the capital in the heyday of Koguryo.