The Mainland is divided into three principal regions (Lower, Mid, and Upper) that are further organised into eight sub-regions: Lowest Lower, Mid Lower, Upper Lower, Lower Mid, Central Mid, Upper Mid, Upper, and the City. The Upper Region (within the broader ‘Upper’ Uji) is positioned as the transition between City Korai and the rest of The Mainland.

Unlike the uniform housing grids of the Lower and Mid regions, the Upper Region is defined by architectural variation and privately commissioned homes. The residential enclave also benefits from embedded commercial institutions. Atelier Yard hosts a cluster of clothing makers; housing the Calcite Textiles and Dadi Garment workshops among smaller attire providers. Beyond this, The Commerce Zone on the east side of The Upper Region provides ample allotments for established artisans; ranging from specialty jam-makers to master furniture craftsmen.

The sub-region also accommodates essential production facilities, including the Oolist Water Aqua Processing Facility and Ozai Ink Incorporated. Together, these institutions position The Upper Region as the pinnacle of commercial production — bridging The Mainland's Mid and Lower regions with the finery of City Korai.