The fortifications are vast. It will take a few hours to walk round along the walls. It is quite an exercise as a big part of it is a hill. But the areas have been nicely done up, so it is very pleasant, though the ugly modern Suwon skyline is always around everywhere. Most of the buildings have been rebuilt but it is nicely done. The originals are not really very old to start with, just over 200 years old. You can get to Suwon on the Seoul metro. From Suwon station, it is a 30-minute walk across the city centre, or you can take a bus. There are many.