With the summer humidity fading and a refreshing breeze settling in, September is one of the best times to leave air-conditioned cafes behind and enjoy the season’s festivals and events firsthand.

At 9 a.m. on the 27th, the grassy area in front of the Yeouido Hangang Park cruise ship terminal in Seoul was packed with 3-4 person mats, leaving no room to step. Citizens had gathered to watch the * ...