Astraea Hill is the main setting of the series. This is where the
three schools are located. The hill is known as a sacred area which no men are allowed to enter. A prominent feature is a very large Catholic church in the center of the hill near a small lake; the church can be seen from a long distance away. There is a horse ranch at Spica. The students may go and study for their classes at a library on the lake's shore. Although only implied in the anime, the manga explains that the library building has another name, "The Secret Garden". It is well-known on campus as a rendezvous for secret lovers.
Students living on campus occupy a dormitory referred to as the "Strawberry Dorms", although its correct name is Astraea Dormitory, named after Astraea Hill. The building is a triangular shape, allowing for the segregation of students from the three schools; each section is about the same size. It was built about 100 years before the story begins, around the same time that Miator was established, for students whose homes are far away. Each student is assigned a roommate in their year until graduation. The building's name is based on its similarity to the cross-section of a strawberry viewed from above.