The Hakurei Shrine is the shrine in Gensokyo that sits along the edge of the Gensokyo Border, helping keep the Border in place so Humans don't wander in.
The shrine is Home to Reimu Hakurei, the resident shrine Maiden, and many people often visit. Suika Ibuki the Oni also lives here, Marisa Kirisame the Witch often Visits, and Yukari Yakumo often visits as well.
Besides the normal Visitors, sometimes Remilia Scarlet and her group come to visit, as do others. Fights sometimes happen.