The Abalone Funeral Dirge takes place in Namimori, a spread-out city seperated into three distinct sections somewhere in the southern half of Japan. This city is broken up between three distinct sections that used to be individual towns many decades ago.
Namimori Downtown The focus of the plot and the heart of the town. Has sprawling residential and shopping districts. Kokuyou Street Industrial, corporate, and tourist sectors. Gets sleazier the deeper you go, but the community is overall very wholesome. Has a lot of internet cafes. Hakuyou A bedroom community, mostly for those who work in Kokuyou. The base of operations for the Akiyama yakuza, and home of the two clans that compose it. Very quiet, insular, and full of people with a very 'watch your own' attitude.
Other locations include... Clinic An under-the-table clinic frequented by people who want to hide their injuries (mostly yakuza). Has a rescue centre for people who get lost on the mountain. Tsuna and Miki's family doctor works here. Kokuyou Healthy Land A Kokuyou-owned property that used to be an amusement park, which in turn used to be a hospital. Known as Japan's Mafia Land when it was still running. Sunflower River A river that stretches through the Greater Namimori area all the way to Miyazawa, where it emerges in the Graveyard of Churches. A great deal of it is underground. Southern Cliffs Rumoured to be the battlefield of Sicilian immigrants and famous Japanese yakuza figures fighting off an unknown threat. No one knows how that works. It's just an old wive's tale, more or less.
Beyond Namimori, there is also:
Tokyo Heart of international relations in Japan, and absolutely crawling with people with secret powers. Miyazawa A little resort town by the sea two hours out of Namimori that holds an ancient ruin by the name of The Graveyard of Churches. Used to be full of European immigrants around eighty years ago.