In Ganghwa-eup are the remains of the small palace built in 1231, once surrounded by an 18km fortress wall. The fortress was destroyed in 1866 by French troops, who invaded Korea in response to the execution of nine French Catholic missionaries. Some 2km of walls and three major gates have since been renovated. It's a 10-minute walk from the bus terminal.
Directly down the hill from the palace is Ganghwa Anglican Church (c 1900), built in traditional Korean-style with arched-tiled roof. Follow the alleyway down to the Yongheunggung Royal Residence , where King Cheoljong used to live.
