Alcatraz Island, San Francisco
The idea of creating a map based off of Alcatraz Island was being pushed by members of Visceral since the main portion of Battlefield Hardline was wrapping up development around late 2014. Given the history of island, and due to most of the team being fans of the 1996 film The Rock, it was decided that Alcatraz would make a great map fitting with Hardline's Cops and Criminals theme.
The map is very heavily based on the real location, with the 30 man team working on the map actually visiting the island and getting "thousands of photos, hundreds of 360 panoramas, and hours worth of audio recordings." The island itself is also on a 1:1 scale with the real life location, with the dimensions being directly translated into the Frostbite engine. Graffiti left over from the 1969 Occupation of Alcatraz was also implemented on the map, and island being under restoration during the team's visit in 2015 allowed them to add repair equipment and materials that players could use as cover on the map.
However, due to the fact that Alcatraz was originally built as a military fort in 1853 and later converted into a federal prison in the 1930s, the island has "incredibly strong tactical fortifications" in real life, so the real layout of the island's structures was not balanced at all for gameplay in Hardline. Several fictional additions were created to address this, including new entrances and stairwells along with better pathing for players. The fictional shower area that was prominently featured during a shootout scene in The Rock was also added, in tribute to the film's inspiration on the map's creation.