The Ambarkanta maps refer to a set of five maps and diagrams drawn by J.R.R. Tolkien and associated with his work "Ambarkanta: The Shape of the World" (a text attributed to Rúmil). The maps were reproduced in The Shaping of Middle-earth (1986).
Diagram I of the Ambarkanta maps details the shape of Arda before the Changing of the World, from West to East and from zenith to nadir. The great mass of land making up much of Arda is named here as Ambar, the earth. The farthest reaches of Ambar are designated Númen and Rómen, West and East. The central landmass of Ambar is here named Pelmar as well as Ambarendya. The midmost point is named Endor. To the west and east of the central landmass is written Ear, the seas. Spanning from the west shore of the west sea to the east shore of the east sea is Vista, the lower airs. In these airs is written Aiwenore, "Bird-land", and above it is Fanyamar, "Cloud-home". Above Vista and all around Ambar is Ilmen, the upper airs. These can be seen to cover the lands of Aman and the Uttermost East, spanning also beneath Martalmar, the roots of the Earth. Written in the span of Ilmen are its other names, Tinwë-mallë and Elenarda, meaning "Star-street" and "Stellar Kingdom" respectively. Surrounding all of Ambar is Vaiya, the Encircling Seas. Beyond Vaiya there is only Kúma and Ava-Kúma, the near and outer Void. Separating Vaiya from Kúma are the Ilurambar, the Walls of the World pierced at Ando Lómen, the Door of Night in the West. At the very bottom of the diagram is written Ilu, an early name for the world of Arda.:242 - 243
Vaiya, that flows completely around the world, forms a sea below it. Ulmo the Lord of Waters dwells in Vaiya, below the Martalmar. Much later, some pencilled changes and additions give Earambar for Ilurambar, Hidden Half right under Martalmar and Arda for Ilu in the title. Pencilled notes at the right-hand bottom corner is too faint to make out after the words "Alter story of Sun" ; that on the left reads : "Make world always a globe but larger than now. Mountains of East and West prevent anyone from going to Hidden Half". :242 - 243
Diagram II of the Ambarkanta maps details the shape of Arda before the Changing of the World, from North to South. Once again, Ambar is shown to consist of Endor at its upper regions and Martalmar in its lowermost depths. Vista covers Endor from the north to south, with Ilmen surrounding all of Ambar, though much less so in the north and south than in the west and east as shown before. Vaiya encircles all the world of Ilu, separated from Kúma by the Earambar. To the farthest reaches of either end of the world there is written Formen and Harmen, North and South.:244 - 245
Diagram III of the Ambarkanta maps details the shape of Arda after the Changing of the World. Here the entirety of Ambar is made round: the Old Lands of the flat Arda now make up one half of Arda made round, and the New Lands are made to form Arda's other half. Vista becomes the lower atmospheres, while Ilmen becomes the upper atmospheres and the regions of outer space. Valinor and Eressëa are shown here to dwell within Ilmen. Beyond Ilmen there is still Vaiya, and the voids beyond it. Passing away from the curvature of the earth and into Valinor within Ilmen is the Straight Path.:246 - 247
Map IV of the Ambarkanta maps details the lands of Arda after the fall of the Two Lamps and before the War of the Gods. The waters and airs of Vaiya and Ilmen can be seen encircling the lands, with the Chasm of Ilmen separating the earth from Vaiya. In the region designated "West - Númen" lies Valinor, and the city of Valmar. The far northeast and southeast regions of Valinor are named here as Eruman and Arvalin. Along the coasts is written Westland or Westerness. In the middle of Valinor on the east coast is the city of Tún, near to the mountain of Taniqetil. Running to the north and south of Taniquentil are the Mountains of Valinor, and on the coast of the Bay of Elfland is Eldaros (Elvenhome). A string of islands called The Enchanted Magic Isles and the Shadowy Isles lie to the east of Valinor within the Belegaer or Great West Sea.
Valinor is separated by Pelmar or Middle-earth in the east by the Straits of Ice in the south and the Helkarakse in the north. In the very northernmost regions of Middle-earth near to the Helkarakse is Falasse, the western coast of Beleriand. Running along the northern regions of Middle-earth are the Iron Mountains, barring Utumna from the rest of the world. On Beleriand's eastern borders run the Blue Mountains, mirrored on Middle-earth's eastern side across the Northlands by the Red Mountains. In the south of the Northlands between the Blue and Red Mountains lies the Sea of Helkar, and on its eastern end there is Kuivienen. In the very center of Ambar near the west of the Mid-land there is written Earth-middle and Endor. East of the Mid-land are the Mountains of the Wind, the western border of Hildórien. In the Southland of Middle-earth is the Sea of Ringil, between the Grey Mountains in the west and the Yellow Mountains in the east. The southernmost point of Middle-earth is marked South and Harmen.
To the east of Middle-earth are the Lands of the Sun, called also the Eastlands or Easterness. Separating the two continents is the East Sea, two more Straits of Ice lying at the northernmost and southernmost ends. In these lands lie the Mountains or Walls of the Sun. The farthest east point of Ambar is designated "East - Rómen".:248 - 249
Map V of the Ambarkanta maps details the lands of Arda after the War of the Gods and before the Changing of the World. Surrounding the lands of Arda are the Outer Seas' of Utgarsecg, the Old English name of Vaiya. Here Aman and the Outer Lands (Valinor) are shown again in the west of the world, with the regions of Araman in the north and Arvalin in the south. A little south of Araman are the havens of Alflon. In the center regions of Aman are the Two Trees, Tún, Valmar, and Taniquetil. To the east of the shores of Valinor lies the Bay of Faery. At its northernmost point, the lands of Aman are still linked to the Hither Lands by the Helkaraksë, leading across the northern regions of Belegar the Great Seas. Given here also is the Great Sea's Old English name Ingarsecg.
In this map, details of the lands of Beleriand can now be seen. The lands of Hithlum and the fortress of Angband and Thangorodrim lie to the north near Daidelos, the northern wastes. Dividing the northern and southern regions of Middle-earth is the Great Gulf (possibly named here also as Beleglorn), with the Straits of the World linking the Gulf to the Inland Sea.
To the southwest of the world lie the Dark Land (South Land), separated from Middle-earth by the expanded East Sea. In the far east of the world lie the Burnt Lands of the Sun, along with the Walls of the Sun near to the western shores.:250 - 251
In The Lost Road and Other Writings (1987), Christopher Tolkien provided additional, redrawn versions of the regions of the furthest North in Map V, in order to "enlarge and clarify..., adding letters to make references to it plainer." Here can be seen the closeness of Hithlum and the Helkaraksë to the Chasm of Ilmen at the edge of the world. Also shown is the river Sirion and the firth of Drengist cutting into the mountains of Hithlum. Not far to the northeast of Hithlum lies Angband and Thangorodrim, and to Hithlum's southeast lies the realm of Dorthonion and the hidden city of Gondolin.
- J.R.R. Tolkien, Christopher Tolkien (ed.), The Shaping of Middle-earth, "V. The Ambarkanta"
- J.R.R. Tolkien, Christopher Tolkien (ed.), The Shaping of Middle-earth, "V. The Ambarkanta: Of the Fashion of the World"
- J.R.R. Tolkien, Christopher Tolkien (ed.), The Lost Road and Other Writings, "Part Two: Valinor and Middle-earth before The Lord of the Rings, VI. Quenta Silmarillion", pp. 270 - 271