Bokko (没庫) is a port city on a small island that is part of the kingdom of Sou. The island is also close to coast of the kingdom of Kou. The town is part of a longer sea route that connects Sou to En via the kingdom of Kei.
The anime depicts Bokko as a city with a harbour surrounded by mountains. Most of the city is built on the terraced cliffs above the harbour. The city is notable as the location where Suzu goes after leaving the port city of Eisou (永湊) in Sai on her way to Kei. Bokko is also where Suzu meets Ikuya Asano, who had been travelling with a group of shusei, and Seishuu as they all begin their journey to Kei.