Take Subway Line 3 (Orange) to Anguk Station. Exit 3 and go straight until you see the main gate. Tickets are to the left of that. This palace only gives guided tours for around 2,200 won or 2 dollars. Can't beat the price. It is open everyday except Tuesday. The English tours are at 11:30, 1:30, and 3:30. The tour lasts about two hours. It was hard for me to understand the guide and sometimes I felt rushed by the group. However, it is the most beautiful palace in Seoul.
The palace was built in 1405 by King Taejong as a detached palace of Gyeongbukgung. Because of invasions and fires, it has been rebuilt five times. The buildings are vibrant and kept in pristine shape. The insides of the buildings are also better perserved then the other palaces. Biwon, or the secret garden is the highlight of this palace. Majestically crafted structures melt serenely into the lush green environment and sit handsomely on the edge of lily ponds. The garden is perfect example harmony between nature and human construction.
I went on a rainy day in October during the Chu-sok Holiday. Even in being soaked could not damper how wonderful it felt to be in this palace. It is gorgeous and pristine. It felt powerful to imagine queens and kings walking in their glory around the grounds.
In 1997, this palace was chosen as a UNESCO World Cultural Heritage List, and it definitely deserves the ranking.