Darkmoon Island
Previously existing as an unnoticed island sitting off the northwestern coast of Kasei, the island became the birthplace and key lair of Team Umbra , an organization that would go on to bring the region to its knees in its bid to destroy the whole of reality. Following the destruction of Umbra's super-weapon, the Deimos Trigger, and ultimate defeat and disbanding of Team Umbra, a clean-up and recovery effort led by Team Terra successfully made the island hospitable again. Shortly thereafter, the Kasei League took control of the island, and opted to build the Kasei League Hall directly atop the site of Umbra's final defeat.
Presently, Iced Flamingo offers a beach-side ferry service to the island that lets trainers off at the entrance to Victory Road, where they can embark on the perilous trek to the League and the Elite Four.