There are several 'hub' locations around Nippon, each of which is linked to at least three other areas. Access to each new hub is initially blocked, but later enabled by gaining more Celestial Brush techniques or completing a specific minigame or subquest. All hubs have a Guardian Sapling, a constantly re-spawning supply of Demon Scrolls, several Devil gates, an Ultimate Origin Mirror, and a Mermaid spring which is usually hidden until clearing a nearby Devil Gate.
There are four major game hubs: Shinshu Field, Taka Pass, Ryoshima Coast and Kamui. Each of these has a number of optional subgames and sidequests, including a Wanted List that can be cleared from its Demon Scrolls, and is linked to a major settlement with many people in it. Onigiri-sensei's three Dojos are all in major hubs, except for Taka Pass.
Agata Forest and the North Ryoshima Coast both have the basic hub features initially listed. Each location also has some extras that are not shared by all of the major hubs, such as Fishing or one of the Devil gate trial caves.