Suburban Catalyst

Suburban Catalyst (HM1P3E)

Location: Pittsburgh, PA 15206 Allegheny County
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Country: United States of America
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N 40° 27.546', W 79° 55.511'

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— The Pennsylvania Railroad Mainline —

You are standing above the historic route of the Main Line of the Pennsylvania Railroad—one of the most important railroad corridors in the country.

The Main Line, which first connected Philadelphia and Pittsburgh in 1852, is significant locally for fostering the growth of some of Pittsburgh's earliest suburbs. Shadyside and East Liberty, the two neighborhoods connected by the South Highland Avenue Bridge—the bridge at your feet—were largely farmland until the PRR arrived—and with it, commuter service to downtown.

Soon the world's wealthiest industrialists were moving their families here beyond the smoky working-class districts. In 1868, the Main Line spurred annexation into the city of twenty-one square miles of rapidly expanding East End Suburbs.

By 1876, the first bridge on this site was completed as part of a program to improve safety by eliminating at-grade crossings. Over the years, the bridge was reinforced a number of times, in part to accommodate heavier streetcar and automobile traffic. The superstructure was replaced in 1925 and again in 2013, though the 1876 stone pier and abutments remain underneath.

Rail travel declined in the early 20th century as the automobile increased access to more remote suburbs. By the early decades of the 21st century, what was once the four-track Main Line was carrying Norfolk Southern freight trains and daily Amtrak passenger trains on two tracks with bus riders commuting on the adjacent East Busway.
HM NumberHM1P3E
Year Placed2013
Placed ByFederal Highway Administration, Pennsylvania Department of Transportation, City of Pittsburgh
Marker ConditionNo reports yet
Date Added Thursday, November 5th, 2015 at 5:01am PST -08:00
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Locationbig map
UTM (WGS84 Datum)17T E 591129 N 4479269
Decimal Degrees40.45910000, -79.92518333
Degrees and Decimal MinutesN 40° 27.546', W 79° 55.511'
Degrees, Minutes and Seconds40° 27' 32.76" N, 79° 55' 30.66" W
Driving DirectionsGoogle Maps
Area Code(s)412
Which side of the road?Marker is on the right when traveling South
Closest Postal AddressAt or near 178 S Highland Ave, Pittsburgh PA 15206, US
Alternative Maps Google Maps, MapQuest, Bing Maps, Yahoo Maps, MSR Maps, OpenCycleMap, MyTopo Maps, OpenStreetMap

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