The Alta Telegraph Company was a telegraph company which operated in the mid-19th century within the state of California prior to the construction of the Transcontinental Telegraph. It was incorporated in the early 1850s. Its first line was constructed during 1854, stretching from Sacramento to Marysville and extending up into the foothills of the adjacent Sierra Nevada mountains. In subsequent years, a line was constructed between Sacramento and Benicia. From Benicia, a branch line was extended to Vallejo and the US Navy yard at Mare Island.
In April 1859, a cable was run across the Carquinez Strait between Benicia and Martinez, and a connecting line constructed from Martinez to Oakland over the Berkeley Hills (then called the Contra Costa Range). It was this line which gave rise to the name "Telegraph Road" for the thoroughfare which the line followed down the western slope of the hills, which later became Telegraph Avenue in Oakland and Berkeley.