A sketch of Penn Avenue (labeled just “Penn”) appears in the margin of John Campbell’s plan of lots in 1764, leading east-northeast from Fort Pitt, just six years after the British captured the Point from the French. It was fully incorporated into the street grid twenty years later when George Woods laid out the first town plat; Woods named it Penn Street. It is named for William Penn (1644–1718), founder of Pennsylvania.[6, 7, 8, 9]
Penn Street became Penn Avenue around 1870, shortly before Liberty Street became Liberty Avenue. The 1862 Beers map of Allegheny County showed Penn and Liberty Streets. George H. Thurston’s 1869 directory of Pittsburgh, in its street directory, listed “Liberty” and “Penn” (implying that they were called streets). The 1870 and 1871 editions listed Penn Avenue but still just “Liberty.”[3, 10] The 1872 directory was the first to list Liberty Avenue. The 1872 Hopkins atlas of Pittsburgh showed Penn and Liberty Avenues.
Atlas of the cities of Pittsburgh, Allegheny, and the adjoining boroughs. G. M. Hopkins & Co., Philadelphia, 1872. http://historicpittsburgh.org/maps-hopkins/1872-atlas-pittsburgh-allegheny; 1872 layer at http://esriurl.com/pittsburgh.
Boone, H. Directory of Pittsburgh & Allegheny Cities, the Adjacent Boroughs, and Parts of the Adjacent Townships, for 1871–72. Geo. H. Thurston, Pittsburgh, 1871. Historic Pittsburgh 31735033431283.
☞ Street directory, pp. 29–41 (Historic Pittsburgh 31735033431283).
Boone, H. Directory of Pittsburgh & Allegheny Cities, the Adjacent Boroughs, and Parts of the Adjacent Townships, for 1872–73. George H. Thurston, Pittsburgh, 1872. DonsList.net PghAllegh1872CDM; Historic Pittsburgh 31735055722825.
☞ Street directory, pp. 3–16 (Historic Pittsburgh 31735055722825).
Campbell, John. Plan of lots in Pittsburgh—1764. 1764. Reproduced in William G. Johnston, Life and Reminiscences from Birth to Manhood of Wm. G. Johnston, The Knickerbocker Press, New York, 1901 (Google Books N-QEAAAAYAAJ); in George T. Fleming, “Flem’s” Views of Old Pittsburgh: A portfolio of the past precious with memories, Geo. T. Fleming, Pittsburgh, 1905, p. 5 (HathiTrust 011204797, 100770599; Historic Pittsburgh 31735056290277; Internet Archive flemsviewsofoldp00flem; LCCN 08028848); in George T. Fleming, “History from an old map,” Pittsburgh Gazette Times, July 16, 1922, second section, p. 2 (Newspapers.com 85913850); in George T. Fleming, Fleming’s Views of Old Pittsburgh: A portfolio of the past, Crescent Press, Pittsburgh, 1932, p. 10; in George Swetnam, “Ferry Street historic, one of oldest in city,” Pittsburgh Press, Nov. 25, 1954, p. 16 (Newspapers.com 149015965); and in Bob Regan, The Names of Pittsburgh: How the city, neighborhoods, streets, parks and more got their names, The Local History Company, Pittsburgh, 2009, ISBN 978-0-9770429-7-5, p. 57. This map is often called the “military plan of Pittsburgh.”
Carlin, Margaret. “How our streets got their names.” Pittsburgh Press, Feb. 6, 1966, Pittsburgh’s Family Magazine, p. 10. Newspapers.com 149098376.
DeLaney, James K. “Spectres of past haunt Pittsburgh’s corner signposts: Street names ‘pennants of tribute.’” Pittsburgh Post-Gazette, Mar. 30, 1967, Daily Magazine, [p. 1]. Newspapers.com 88235360.
Fleming, George T., ed. Pittsburgh: How to see it: A complete, reliable guide book with illustrations, the latest map and complete index. William G. Johnston Co., Pittsburgh, 1916. Google Books 02NAAAAAYAAJ; Internet Archive bub_gb_02NAAAAAYAAJ.
Regan, Bob. The Names of Pittsburgh: How the city, neighborhoods, streets, parks and more got their names. The Local History Company, Pittsburgh, 2009, p. 72. ISBN 978-0-9770429-7-5.
Thurston, George H. Directory of Pittsburgh & Allegheny Cities, the Adjacent Boroughs, and Parts of the Adjacent Townships; for 1870–71. Geo. H. Thurston, Pittsburgh, 1870. Historic Pittsburgh 31735055723153.
☞ Street directory, pp. 29–35 (Historic Pittsburgh 31735055723153).
Thurston, George H. Directory of Pittsburgh and Allegheny Cities, the Adjacent Boroughs, and Parts of the Adjacent Townships; for 1869–70. Geo. H. Thurston, Pittsburgh, 1869. Historic Pittsburgh 31735038288522.
☞ Street directory, pp. 3–9 (Historic Pittsburgh 31735038288522).
Woods, George. A draught of the town plat of Pittsburgh, surveyed for John Penn, Jr., and John Penn, by George Woods, May 31st 1784. 1784. Reproduced as “Original plan of Pittsburgh” in plate 19 of Atlas of the cities of Pittsburgh, Allegheny, and the adjoining boroughs, G. M. Hopkins & Co., Philadelphia, 1872 (Historic Pittsburgh 1872p019).