The Kumsusan Palace is one of the most unique places to visit in the whole of North Korea, and also the most sacred. For there, housed within its walls, the Dear Leader Kim Il-sung and the Great Leader Kim Jong-il bodies are embalmed and lying in state.
When I visited back in 2009, the Great Leader was still alive, so only the Eternal President, Kim Il-sung's body was there. On the second visit in 2012, the palace was undergoing renovations to make room for the recently deceased Great Leader, Kim Jong-il, and was not open to the public.
Cameras and photography are expressly forbidden inside, and so unfortunately I have no photos to share of this incredible experience. If you'd like to learn more about its interesting history and what's inside, there's some pretty decent information on Wikipedia already.
Being such a sacred and important place, everyone dresses up when they go there. Just as you might dress for a funeral in the US. In North Korea, the women wear their Choson-ot while the men wear their military uniforms. As a foreigner, I wore dress pants, dress shirt, and importantly, a tie. If you are improperly dressed you will not get inside, but the experience inside is one for the books.
The palace of Eternal President Kim Il-sung, where his body remains lying in state with that of his son's, Kim Jong-il.