A: Boston, Massachusetts, United States, B: Somerville, Massachusetts, United States
Construction of the first regular telephone line was completed in 1877. It ran from Boston to Somerville, Massachusetts. Also in 1877, the first telephone switchboard was set up in Boston. On February 12, 1878 Bell's father-in-law Gardiner Greene Hubbard, Thomas Sanders, and George L. Bradley, with money from investors in Massachusetts and Rhode Island, set up the New England Telephone Company at 43 Sears Building, Boston. One year later "New England Telephone and Telegraph merged with the Bell Telephone Company (which was started on the basis of holding "potentially valuable patents"), on February 17, 1879, to form the National Bell Telephone Company, at which time Theodore Vail took over its operations. The National Bell Telephone Company merged with others on March 20, 1880 to form the American Bell Telephone Company" (Wikipedia aritcle on New England Telephone and Telegraph Company).