Harrisburg lies on a broad swath of the great Susquehanna River, punctuated with its distinctive bridges. Founder John Harris ventured beyond the frontier and established a ferry in 1733 that ushered the pioneer migrants as they trickled west. Many stayed on to establish a city that became the legislative seat of America's most industrious state. The unusual vintage postcards in Harrisburg illustrate the history of a city that played an important...