Shipping magnate John D. Spreckels used his wealth to build great hotels, expand transportation facilities, establish a business district and to develop San Diego’s cultural features. One of those features was an elaborate seaside and bayside resort at Mission Beach. An area was selected in 1922 for an amusement center, dance casino, bath house with a plunge, provisions for surf bathing, concessions, a roller coaster and a miniature San Diego & Arizona Railway system. Three years later, the carnival-like amusement center, later known as Belmont Park, opened to considerable public interest with its tent city, much like that near Spreckels’ Del Coronado Hotel.  The question of obtaining adequate transportation for larger crowds was brought to the builder’s attention.  Since he operated the ever-expanding San Diego Electric Car Co., why not establish a streetcar line? First, a shuttle service with two old street cars was installed from the Ocean Beach line to a track from the defunct Bay Shore Railroad Company.  This included a bridge across the channel that had been built in 1914.   Eventual plans called for a new electric railroad line from Kearny Boulevard and Broadway in San Diego all the way to Mission Beach.  The bridge was restructured to accommodate  the consistent travel. On  Sept. 8, 1923, the San Diego City Council accepted the bid of the San Diego Electric Railway for the new line.   In doing so, Spreckels had  given San Diego one of the finest electric streetcar systems in the country for a town its size. “It was just plain business sense,” Spreckels would reflect. “The city would not grow without an abundant water supply and adequate streetcar facilities.”   People in La Jolla, without rail transportation since the folding of the Los Angeles-San Diego Beach Railway, clamored for electric trains and a line extension.  The old railway tracks were used to reach La Jolla’s Fay and Prospect streets.   An attractive building was built at La Jolla Hermosa for the San Carlos substation.  Following the construction of the Ocean Beach substation building — with Egyptian design — a similar one was erected in Mission Beach. With the opening of the new line to the beaches, service via the Point Loma Railroad  to Voltaire Street in Ocean Beach was abandoned. That section of the line would be served by buses starting in 1938. What had become an interurban line in 1924 to Mission Beach and La Jolla ended dismally on Sept. 16, 1940. Automobile traffic from an expanding population slowed this rapid transit to a crawl. The streetcars were too heavy, slow, complicated and noisy.  La Jolla’s terminal was razed, the elaborate over-crossing tresses were torn down and all the rails removed except those in paved streets.  A few lines remained in other parts of the city until 1948.