Hill Valley, California, is the fictional setting for the Back to the Future films.

The town was first settled in about 1850, and in 1865 became a city. By the 1880s the railroads had reached the town and the small settlement was growing. Construction of the courthouse began in 1885 and the Shonash Ravine Bridge in 1887. By 1955 the town was in its heyday, with a grass-covered town square right in front of the courthouse. A popular place to hang out was Lou's Cafe; other businesses included Ruth's Frock Shop, Texaco, Roy's Records and the Essex theater.

On November 12th 1955 at 10.04 pm lightning struck the clocktower, freezing the clock at 10.04 pm where it would remain for at least the next 60 years, despite many attempts to repair it. The Hill Valley Preservation Society believed it should remain stopped as a symbol of its history and heritage.

By 1985 Courthouse Square was but a shadow of its former self. Since Twin Pines Mall opened, a lot of the businesses had relocated there or shut down, and the Square was full of adult book stores and second hand shops. On October 26th 1985, local inventor Doc Brown invented a time machine built into a DeLorean sports car, and his young friend Marty McFly was accidentally sent back to 1955. Marty interfered with his parents' first meeting but managed to get them back together, and using the lightning bolt that struck on November 12th got back to the future, only to discovert that because of his interference, his father George McFly was now a confident sci-fi author rather than a geeky office worker.

It is in the future though that Hill Valley regained its heyday. By 2015, the town square is once again a grassy park with a lake, and shops had returned to the square. The courthouse has been converted into a mall, and the clock is still stopped at 10.04pm. The future for this little town in California looks bright indeed.

We also see an alternate history in Hill Valley. In 2015, Biff Tannen steals the time machine, goes back to 1955 and gives his teenage self a sports almanac with the results of every sports game from 1950 to 2000. Using this book, Biff became incredibly wealthy. In 1973 he murdered George McFly and married his widow, Marty's mother Lorraine Baines McFly. Gambling was legalised in 1979 and Biff turned the courthouse into a casino-hotel. Luckily, Marty and Doc went back to 1955 and got the almanac from young Biff, thus returning history to normal.

Hill Valley is located in Northern California, 12 miles east of Grass Valley and with railway links to San Francisco. The town is nestled in rolling foothills, and (according to details in part 3) although there is a desert within walking distance of the town, the nearby lake freezes over in the winter.

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