Seoul has been surrounded by walls that were built to regulate visitors from other regions and protect the city in case of an invasion. Pungnap Toseong is a flat earthen wall built at the edge of the Han River, which is widely believed to be the site of Wiryeseong. Mongchon Toseong () is another earthen wall built during the Baekje period that is now located inside the Olympic Park. The Fortress Wall of Seoul was built early in the Joseon dynasty for protection of the city. After many centuries of destruction and rebuilding, about  of the wall remains, as well as six of the original eight gates. These gates include Sungnyemun and Heunginjimun, commonly known as Namdaemun (South Great Gate) and Dongdaemun (East Great Gate). Namdaemun was the oldest wooden gate until a 2008 arson attack, and was re-opened after complete restoration in 2013. Located near the gates are the traditional markets and largest shopping center, Namdaemun Market and Dongdaemun Market.