Academy City

Academy City is the city where most of the series takes place.

Located west of Tokyo, it is a semi-independent city led by the 12 members of the Board of Directors, which are then, supervised by its founder Aleister Crowley. As the city's name suggests, it is a city of several schools and institutions of higher learning from kindergarten to university level that learn side by side along with the scientists who research on psychic powers and higher technology. The city's size is a third of the Tokyo metropolis. The city was founded by the magician Aleister Crowley to do studies and research on the development of preternatural abilities. Where the city's funds comes from is probably from different countries, even the military, that have high interest in psychic research. Also, the city has other bases of operations outside of Japan such as in Russia.

Academy City is composed of at least 19 Districts, some of which have specific purposes; District 7, for example, contains the majority of middle-school academies.

Demographics
The prologue of Volume 1 of the light novels specify the demographics of Academy City; its total population is about 2.3 million with 80% of them being students and 1/8 of those students living in the city dorms. Of the entire student population, about 60% of them have the ability to demonstrate even a slight amount of psychic ability (these are Power Users of Levels 0-5). The remaining 20% of the students in Academy City pursue other subjects instead of going under the Power Curriculum Program, like Tsuchimikado Maika, who studies in a maid school.

Security
Academy City's technology is thirty years ahead of its time and thus, has accessibility to a more sophisticated array of measures to ensure security across the city.

The city limits leading outside are lined with walls, accessible only through entry points which require persons to have permission to enter or leave the premises. Inside the city, hidden cameras are dotted along every road and alleyway. This, in turn, can be accessed by the peace and order groups in the area, Judgment and Anti-Skill, to check if there are any crimes occurring.

In addition to the ground-level security protocols in Academy City, the satellite Orihime 1 (where the Tree Diagram supercomputer is located) and Akaboshi 2 (a camera satellite and also a satellite laser-cannon) gathers detailed pictures of the area and relays it back to Earth.

The primary peacekeeping forces in Academy City are Judgment and Anti-Skill; these two groups are composed of trained students and faculty respectively which deal with crimes and conflicts with security.

Unfortunately, security in Academy City is revealed to have severe flaws in it. Because of the destruction of Orihime 1 in Toaru Majutsu no Index, live feeds of satellite images are greatly reduced. Magicians can easily enter Academy City and, like Sherry Cromwell, can cause damage despite the presence of Judgment and Anti-Skill units. Also, in Toaru Kagaku no Railgun, it has been revealed that District 10 of Academy City has been completely overrun by its inhabitants, unreachable by technology due to the Skill-Out members destroying the hidden cameras throughout the district.

Though there are other forces like the HsPS-15 armoured AI, other advanced technology, and groups like MEMBER and ITEM, they are mostly politically motivated factions working for one of the 12 Board of Directors of Academy City or Aleister Crowley, and care less about security and more on furthering their (or their employer's) own interests.