Jarro is a land divided into 3 main islands. Eastland, Midland, and Westland. These islands share many cultural elements, but each is still fairly unique. Jarro's population is made up of mostly humans, but there are clusters of other races. The primary example being the dwarves that live in northern Westland. The lands of Jarro are also inhabited by sea elves, but they have no permanent residence on land.
Not much is mentioned about Eastland. The book seems to infer that Eastland is a heavily forested land but it cannot be confirmed. The Great Arch of Jarro is near the center of Eastland but isn't shown. One of the cities of Eastland is Shinmar.
Alex meets Joshua, son of King Darthon, while he traveled through Eastland.
The middle island in Jarro, Midland has a large trade industry. Many of its largest cities are coastal cities facing Eastland / Westland. Examples of these cities include Hafnar, Welding, Paralesea, and Denmar. Midland is also home to an oracle tower but not much is given on the topic though it is most likely located in the southern part of Midland. A large portion of information and wealth is shared through a series of caravans that run across large portions of the continent. Midland houses a fairly diverse geography in the north. Ranging from forests to grasslands. Little is known of the southern portion.
Alex meets Lupo while traveling through Midland
The people of Westland are known to be a more militaristic bunch. Many of the cities of Westland have large stone walls and are built to withstand, whether that be an assault or the elements. This is partially due to Westland being divided by threats of war. The main contenders in Westland is the southern kingdom ruled by Kind Darthon, and the kingdom of Conmar, ruled by Jabez. Their are multiple other kingdoms, many of which are in a loose alliance with Darthon. Much of Westland is divided by a group of mountain ranges. These mountains, or somewhere north of them, is where a group of dwarves reside. The sea elves do interact with these other groups, but keep out of direct intervention.
Alex meets Aliia, Karill, Navar, the other sea elf elders, and Jabez while in Westland.