"The wall, which follows the ridges of Baegak (Bugaksan), Naksan (Naktasan), Namsan (Mongmyeoksan) and Inwangsan, the four main mountains surrounding the center of Seoul, has been constantly managed since its initial construction in 1396. The wall measures between 5 and 8m high and is 18.6km long and it bears witness to the role played by a city wall in the life of a capital city, still sustained in modern day Seoul."

Please follow the link below for more information:

The route dates back to the 6th century. It follos the path of Saints Seiriol Wyn and Cybi Felyn who would walk from the opposite ends of Ynys Môn and meet at Ffynnon Cybi in Clorach. The route starts at Caergybi and ends at Trwyn Du, Penmon using mainly back roads with public footpaths where possible and a short section of the coastal path. 

The bicycle and footpath in Jyske Ås starts from Dronninglund Castle and ends at the square in Østervrå. The route was previously part of the Hærvejs route, but this has now been given a different course, so the Jyske Ås path is easily missed due to messing signs in certain places. However, the route can easily be found and is definitely worth a visit.