Even though John Dough and the Cherub clearly indicates that Hiland and Loland are on an island, called Hi-Lo by some and Lo-Hi by others, the map in the Tik-Tok of Oz endpapers shows them as part of the mainland, to the east of Oz.
James E. Haff and Dick Martin restored them to an island while maintaining the same basic location, and presumably so the Deadly Desert wouldn’t then border on the ocean, added in a narrow strip of land with mountains on it.
This makes for a rather intriguing location, a part of the map where no canonical adventures take place. As such, it’s no surprise that some apocryphal works would explore the area. In Phyllis Ann Karr’s Gardener’s Boy, Big Zector’s new country of Zectorland is established in a small valley “in the strip of mountains south of Merryland.” Marcus Mebes’ Skeezik and the Mys-Tree introduces Meerth, a small, run-down country in the area, bordering on the Shifting Sands. At the beginning of this story, it was ruled by King Richard and Queen Rejinah, the latter of whom practiced witchcraft in secret to help the country. She made an enemy of Shielee Prana, a nasty old witch (and possibly a former friend of hers, at least according to a somewhat suspect scene in Magic Tapestry) who was jealous of her and wanted to conquer Meerth.
Shielee sent Rejinah to Oz and turned her into a bat, but she was rescued by her children and their pet Skeezique Fwiirp, with some help from Ozma and Dorothy. The children, also named Richard and Rejinah, took over ruling Meerth, and the place became much more prosperous.
In Melody Grandy and Chris Dulabone’s Thorns and Private Files, the Canadian gander Benny describes Meerth as “a tiny, medieval country…which was rather plain and uninteresting, ‘cept for a nifty castle in the center.” According to Terra Obscura, it also has winged horses. And in my own “The Search for Soob,” there’s a country in the region called Nimenvell, made up of five mountains, the one in the center being the location of the rulers’ castle and temples to the four classical elements on the other peaks.
The most detailed look at the mountainous area, however, is in Jack and Larry Breton’s Ork. As per a map in the book, the majority of the territory is known as the Ivalane Valley, surrounded by the Ive and Moran Mountains.
One of the protagonists of the story, Irving, is the son of the Fourth Squire and Chief Goatherd of the tiny country of Ivalor, known for its goats and their milk. Other lands in the valley are Ranistan (unnamed on the map, but the rain forest is referred to as Ranistanian in the text), Bildad, Arv, the Kingdom of Kallikan, the Duchy of Dantan, and Moran; but we find out very little about these places. We’re told that Ivalor received fabrics from Kallikan and kitchenware from Dantan. The Wisp, a beekeeper with a swarm of nasty wasps, lives in Moran.
He terrorized Ivalor for some time before teaming up with Mombi and Blinkie in an attempt to conquer Oz. I’d say there’s enough room in the area for all of these countries, although I don’t know the exact layout.
Speaking of different interpretations of the maps, I came across this one by John Drury Clark and John Burton Hatcher in the Spring 1978 Baum Bugle. It does something I’d seen a few other attempts at by other hands, specifically wrapping the Nome Kingdom around the northern part of the continent to make the references to its being east of Oz in Ozma work with others in which it’s to the west. As it’s not based on the Tik-Tok map at all (or at most very barely so), it can make Hi-Lo/Lo-Hi an island without the need for the strip of land; but also leaves a lot of unexplored territory to the south of Oz. While clever, it’s obvious that the Tik-Tok map was directly referenced by the canonical authors. giving it more authenticity despite its occasional contradictions. As I’ve mentioned before, however, the Tik-Tok map DOES allow for some unexplored area off its edges, as the ocean is only shown in one little corner. It’s a reference in Ruth Plumly Thompson’s Captain Salt that makes clear there’s very little else there besides ocean.