The Great Mata Nui Highway is a collection of long or unnamed roads that pass though several of the island's major locations.
The Great Mata Nui Highway (or GMNH) is island-spanning, and has no real beginning or end. However, Ga-Koro can be used as a starting point.
Following the Old Fusa Path south from Ga-Koro, the GMNH branches off from the road and loops back north into Po-Wahi, traversing the rocky cliffs along the border of Naho Bay. Further north, the GMNH branches off in two directions - the road continuing north terminates at part of the Path of Prophecies closer to Po-Koro, whereas the western branch brings travelers to part of the Path of Prophecies closer to Po-Wahi's entrance to Onu-Koro.
Continuing along the western branch, the GMNH continues underground, down into Onu-Koro and the Great Mine. The south road out of Onu-Koro brings travelers through the Onu-Ta-Le-Koro Subtransect. After a short distance, the Subtransect branches, with the right-hand tunnel bringing the traveler back aboveground into Ko-Wahi (the road becomes the GMNH again at this point).
The GMNH weaves through Ko-Wahi's mountains and drifts for a short distance until arriving at Ko-Koro.
Continuing south from Ko-Koro, the GMNH continues weaving around Ko-Wahi's mountains and drifts, eventually leaving the mountains behind as the road passes through The Massif, then further south into Le-Wahi and through Kini-Nui.
Past Pala-Koro, the GMNH follows a northeastern arc out of Le-Wahi's jungle, into the Charred Forest, and finally into Ta-Koro. The path north out of Ta-Koro winds through the northern part of the Charred Forest before turning into the Old Fusa Path, bringing travelers back to Ga-Koro.
The Great Mata Nui Highway passes through every Wahi, and so sees most of Mata Nui's biomes. Following the route described above, a traveler will witness winding clifftops, arid grasslands and rocky canyons, underground tunnels, frozen mountains and snowdrifts, glaciers, grassy hills, swampland, dense jungle, grassy clearings, forested lakesides, burnt forests, and more.