Following the San Francisco earthquake of 1906 (retconned as the Great Catastrophe of 1906 in Big Hero 6: The Series), in which scientist Lenore Shimamoto caused the disaster when she attempted to invent a new form of unlimited energy that backfired, Japanese immigrants helped rebuild by contributing key Japanese building techniques that allowed the city to flourish and prevail in the face of the seismic events like never before. Following this restitution, San Francisco was renamed San Fransokyo in honor and recognition of it being a city reborn thanks to a combination of Japanese and American architecture, landscaping and engineering skills. The city's iconic amalgamation of American and Japanese culture followed soon thereafter.
The city of San Fransokyo is an Eastern-Western blend of aesthetics covering a fairly extensive region on the coast of the Pacific Ocean. It is host to such notable locations as the Lucky Cat Café, the Akuma Island, and the San Fransokyo Institute of Technology. Downtown San Fransokyo is where the large majority of the events chronicled in the first film take place. Japanese flora and fauna can also be found across the city, such as Japanese cherry blossoms and Japanese bobtail cats.
Downtown: The heart of San Fransokyo is found in the metropolitan center of the city or "downtown". Several key locations are found here:
Lucky Cat Café: A popular bakery, breakfast, lunch and dinner shop that doubles as the Hamada family home.
Warehouses: Multiple warehouses can be found throughout the city and are used as hideouts for villains.
Good Luck Alley: A district that is known for being the home of criminals, such as Mr. Yama and his henchmen. It is named after the likely chances of people getting out of the alleyway, alive. Momakase's hideout is located there, where the Food Fight competition was formerly held.
Go Go Tomago's Neighborhood: This dangerous place is home of thieves like Dibs. Go Go and Honey Lemon live in an apartment from this neighborhood.