ref: a7dca30971a049a525e33bc43eaf2b18ce899c5e 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