Every company in the world involved with the Pro Hero business invested money to create a technological paradise for the research and development of Quirks and support items. I-Island is an artificial moving island create for scientists to peacefully research together. Thousands of scientists and their families inhabit the island's main cities. Scientists primarily research the Quirk phenomenon and develop tools to support Pro Heroes.
The island was created to gather the worlds top researchers to a safe place where their combined talents could study Quirks. There are several countermeasures in place to prevent criminal incidents. The island's security system is on par with that of Tartarus Prison, many of its structures are built sturdier than bomb shelters, and scientists cannot leave the island to ensure confidentiality. There had never been a villain attack on the island before Wolfram's invasion.
I-Island is also home to the famous I-Expo, a city-wide event that showcases all the island's technological advancements. Pro Heroes are invited by the event sponsors and people are permitted to use their Quirks in public. 
I-Island is completely artificial and mostly built from iron. However, the island comes complete with four different cities separated by large bodies of water and natural foliage. There are beautiful beaches, great lakes, and incredible cities to be explored. The island has a residential district, a business district, and schools. The island can only be accessed via plan by entering through the airport. 
I-Island's primary setting for research and development is the 200 story tower in the center of the island. It was built sturdier than a bomb shelter and is the central command for the entire island.
The central tower hosts hundreds of floors, each with a different purpose. There is an elevator with restricted access and a set of stairs leading to every level. I-Island security is managed from the control room on the top floor. Each floor is secured with shutter doors and special roof hatches in case of an emergency.
There is a reception hall on the second floor. Secret development projects are kept in the storage room and the tower's security signal is broadcasted from the server room. There is also a plant factory on the 80th floor for research on how Quirks affect plant life. The tower is powered by a wind turbine energy generation system. 
The only way to enter I-Island is by flying via plane to its airport located on the out ring of the island. Several planes from various airlines bring people to and from the island. There are also various gates that can be used to board planes. Anyone coming in from the outside must pass a security inspection in the airport. 
During the I-Expo pre-opening, there is a Pavilion open to those with the correct passes. Inside is a beautiful blue museum showcasing super advanced support equipment for Pro Heroes. 
I-Island Security System
- Further information: I-Island Security Bots
The I-Island Security System's efficiency is equal to that of Tartarus, a maximum security prison for supervillains. The system is wired into the entire island and controls both its communications network and the electrical grid.
The system can only be accessed from Central Tower's top floor control room. The control room gives the user full control over the towers functions including closing shutter doors, camera control, and the central elevator. Central command is built like a fortress and can't be broken into.
Countless security drones are used to maintain order throughout the island. They are durable enough to take on Quirks and are efficient at exploiting their limits.
On high alert, the communications network cuts out for citizens, turning off cable and cellular connections. Security bots are used to enforce a curfew and can arrest people on the streets. The system is also armed with restricting devices strong enough to restrain All Might. In the wrong hands, the security system can give someone overwhelming control over the island.