Academy City (学園都市 Gakuen Toshi), also known as Academy City of Science and Technology, is a nation and is the main setting of the entire A Certain Magical Index series including both A Certain Scientific Railgun and A Certain Scientific Accelerator and is the entirely and center of the science side. It is a land-locked sovereing city-state located in the Tokyo Metropolitan Employment Area as an enclave. As its name suggests, the city is filled with schools and is also the home to the best scientific and technological advancments in the world. Unfortunately however, Academy City has been targeted by organizations such as the Roman Orthodox Church of the Magic Side and has been attacked over and over again by corrupt and fanatical magicians. Because of this, Academy City has been protected by both the English Puritan Church and Necessarius who assist Touma Kamijou in his fight to keep the city safe.
In the year 1947, Aleister Corwely was found by a man known as Heaven Canceller afte he discoered Aleister injured in the remote countryside of England. He nursed Aleister back to health and then Heaven Canceller talked about the idea of Academy City based in Japan. Crowley liked it and he eventually founded and created the city for the sole purpose of studying science and technology. Crowley created Academy City and made it so he could analyze and study preternatural abilities and eventually the city became filled with espers. According to Therestina, for years on end, Academy City and its scientists have been trying to find away to make a Level 6 Esper which has led to the deaths of countles students in the past. October 9th is Academy City's Independence Day but its actual date of independence is left unknown.
Academy City is located west of Tokyo, Japan where there is a constant flow of wind as seen by the giant windmills outside of the city which generate much of its power. The city's climate is most likely similar to that of Tokyo and other areas surrounding it. Through the city's technological advances, it is able to predict the weather patterns and gives accurate predictions on how the weather will change. Academy City is roughly around the size of 1/3rd of Tokyo is comprised of 23 Districts refered to as School Districts each with their own purpose and facilities.
Academy City has declared a state of neutrality when it comes to the issues of the Magic and Science Sides and their affairs. It is the center of the science side but does allow Magicians into the city whenever they want to despite their true intentions. This is most likely due to the fact that the city's founder, Aleister, is both a magician and a member of the science side. Despite being the dominate faction, center, and entirerty of the science side, it's plauged with conflict between waring factions of the science side within the city's borders which is different from the conflict going on in the magic side with the various churches. Academy City is the most technologically advanced city in the world in the series and since it can produce supernatural abilities, it has been envied and feared by factions on both sides. Academy City has to abide by International Law and as a result, Cloning is illegal, although the sister clones were able to exist but most likely is secrecy.
Academy City most likely has a very friendly relations towards most countries. It has many institutions based outside of its borders such as in neighboring Japan. Other bases of operations exist outside of Japan including many in Russia where all of the surviving sisters except for 10 were sent to Academy CIty facilities based in Russia in order to have their bodies readjusted for longer lifespans and Misaka 10777 became a member of an unknown Russian Organization and is even a Russian Soldier following the conclusion of the Level 6 Shift Project. Academy City is known for its espers and also has around 50 of them who are Gemstones, espers who have their powers from natural birth, and many nations/factions have tried to hunt them down including the Central Intelligence Agency of the United States. The CIA has even sent in 20 spies to each of the 50 factions trying to hunt down the different gemstones living outside of Academy City. There was an event from September 3s-10th (year unknown) where the students of Academy City could travel to different nations around the world and students from around the world could come to Academy City showing a positive relations with other countries.
While Academy City is neutral on both the science and magic sides, it does have secret connections with magic side factions. For a long time now, the Roman Orthodox Church has longed since tried to take over Academy City even before the series began. Many of its members and magicians have sent out after Academy City with the intent of taking it over as was tried by Lidvia Lorenzetti and Vento of the Front had almost destroyed the city entirely during the Roman Church's invasion of the city. Due to the actions of the Roman Orthodox Church, this has caused the English Puritan Church to get involved and send in its members from Necessarius. Academy City and the Anglican Church have the strongest relationship in the city's foreign affairs as both of them make deals with each other. In return for the Anglican Church's protection of Academy City from the Roman Orthodox Church, the city gives it goods and gifts back in exchange for the English Church's protection. Academy City is also the home of the Kamijou Faction where many magicians are members of the unofficial organization.
The Academy City Board of Directors is a collective body of the leaders of Academy City and is typically lead by Aleister Crowley as the Supreme Superintendent of Academy City and is the de-facto ruler of the nation. Crowely typically doesn't concern himself with government affairs and leads all policies up the 12 Board Members all of whom, are easily expendable and can easily be replaced. The Board of Directors has absolute power in Academy City and all decisions are final since over 80% of the population are students.
Academy City is a landlocked city-state but does contain a military force. Anti-Skill acts as both the police and military of Academy City. They often deal with situations like terrorists and other domestic issues as well as handeling criminals. Anti-Skill Officers are often armed with SWAT Gear and use SG-550 Assault Rifles along with MP5 Submachine guns as their primary weapons. Anti-Skill also handles experimental weapons and has been seen using HsPS-15 Powered Armor Suits in combat. Members have even used tanks and HsP-00 Supersonic Jets during combat and have been deployed to foreign countries in the past. Anti-Skill is able to have such power resources as a result of Academy City's advanced technology and being technologically and scientifically 30 years ahead of the world.
While Anti-Skill does handle crime, it engages in many military activities and much of the police work is handled by a separate organization. Judgment is a police organization and is made up entirely of students. The main goal of Judgment is to assist Anti-Skill by monitoring the students of Academy City (who make up the majority of the population) and keep them safe from criminals and rogue espers that may cause harm to them. Members of Judgment are made up of powerful espers with a diverse set of abilities and has over 177 different branches across Academy City. Judgment is entirely a police force and does virtually all arresting of criminals in Academy City with Anti-Skill bringing them into jail at the end of their capture.