ref: bbc257476f9aac8d04d75a8036d412caa8f7d515 dir: /data/maps/headers/Route20.asm/
map_header Route20, ROUTE_20, OVERWORLD, WEST | EAST connection west, CinnabarIsland, CINNABAR_ISLAND, 0 connection east, Route19, ROUTE_19, -18 end_map_header