Original 1880s cabinet card photo showing men / employees out front of the Western Union Telegraph Office (sign above man with dog). Note the train tracks in the foreground.
Cabinet card is 6.5" x 4.25" with blank back, so no location noted, however this is from a larger collection of old photos
from Lisbon, La Moure and Edgerley North Dakota / Dakota Territory. I think this is possibly the office in Bismarck, which opened in the 1870s.