Despite the name, Hwaseong Fortress is not located in the city of Hwaseong, but in the city of Suwon. From Suwon Station, cross the street and catch any of the buses with a "Hwaseong Fortress" sign on the window.
There is a part of the fortress wall that has a manned ticket booth and will charge an entrance fee. While admission is minimal, there are still other parts of the wall that has no ticket booth and you can enter for free. I found this very confusing, but being a budget traveler, I had to ignore the ticket booth and continue walking until I found a set of stairs where I could enter for free. There is also a palace museum, but I never visited it.
