The Yon region is an area off the northeast coast of Borea. It consists of the three main Yon Islands, and the coastline immediately adjacent to them. It has a cool humid continental climate in the south, ranging to a taiga-like humid subarctic climate in the north. Notable fauna include ailuries, longhaired antelope, mountain tuskers, voles, lemmings, pika, and desmans. The largely-coniferous flora of the region's closed-canopy forest is dominated by larch trees, interspersed with fir, birch, willow, alder, aspen, paperberry, and numerous berry bushes.
The people of the Yon region typically live in small matrilineal clans, dependent on antelope pastoralism and small-scale cultivation of paperberry and tubers. Farmers have also domesticated the Boom Grouse, raised for feathers, meat, and eggs. Many of the peoples of this region speak a language descended from Proto-Yonic. These Yonic languages were long assumed to be unrelated, and thus given an areal name.
Contemporary residents dwell in large, thatched or wood-shingled A-frome longhouses or burdei. Each house has a large central hall dominated by a complex brick oven, with storage above and sleeping quarters to each side divided by curtains or wooden walls. Typically, a longhouse is built over a shallow pit lined with stone slabs or drystone masonry, a remnant of earlier pithouses.