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The Pennsylvania State Route Numbering System
The United States Highway System and Numbering


Before the mid-1920s, state route numbering systems developed in several states. These systems were specific to the state and often had little to do with the numbering systems of neighboring states. These systems posed problems for important roads that cross state boundaries. Upon crossing a state border, the route number would typically change or disappear, possibly causing a little bit of confusion for motorists. The US Highway system was implemented in 1926 to eliminate many number changes at borders and to create a contiguous system of principal highways that would span several states.

In Pennsylvania, the US highways followed several major state routes numbered by the 1925 system. These routes carried both US and state route numbers for a few years until the US highway system was finalized in the late-1920s and early 1930s. In 1928, Pennsylvania altered their state route numbering system to expand mileage and to avoid duplication with the US route numbers. In order to number the child and spur routes of the US highways, state route numbers needed to be reassigned to the US highways. These new state route numbers were probably dually signed with US highway numbers along US highways if the state route numbers were the same as the 1925 numbers. Other parent route numbers were important by themselves but may have become either signed or hidden numbers in multiplexes or overlaps, i.e., where two routes merge together and share a single roadway.

For example, PA 7 was assigned to US 6 from Meadville to New York, allowing the assignment of the signed child routes 107-707 and the signed spur routes 957-963. 45, on the other hand, had sections by itself (e.g., Lewisburg to Water Street) but other sections that overlapped with US routes (US 22, US 220, US 111, US 120 (later US 122), and US 209/US 309).

The details and history of the US Highway system are well documented on the web. One particularly good source is Robert Droz's site, U.S. Highways: From US 1 to (US 830). In addition, Jeff Kitsko covers the history of the US highways in Pennsylvania in his Pennsylvania Highways site. Below is a summary of the numbering rules, a review of the state route numbers assigned to the US highways, and an overview of the renumbering of similarly numbered state highways.

The US highways were numbered according to rules similar to the parent-child system in Pennsylvania.

US Highways
  • Major highways were given one- and two-digit numbers.
  • East-west major highways were given odd numbers, increasing from north to south.
  • North-south major highways were given even numbers, increasing from east to west.
  • The primary major highways were given numbers ending in 0 or 1.
  • Minor highways were given three-digit numbers and connected to major highways with the same last two digits.

In Pennsylvania, the major east-west highways were US 6, US 20, US 22, US 30, US 40, and US 62, while the major north-south routes were US 1, US 11, US 13, US 15, and US 19. The minor or branch routes created families much like the state route families, e.g., US 22, US 122, US 222, US 322, US 422, US 522, and US 622.


State Routes Replaced by US Highways

Pennsylvania's US highways replaced various major state routes, eliminating most of the single-digit routes. The following table summarizes the original routings of the US highways and the state route renumberings that avoided duplicate numbers. Green-shaded routes exist today, blue-shaded routes have been decommissioned, and gray shaded routes either never existed or were 1925-system routes that were eliminated by 1928.

US Highway Hidden state route numbers Duplicated state route Renumbering
1 1 east of Philadelphia and 12 west of Philadelphia. 1 Assigned to US 1 from New Jersey to Philadelphia, to US 30 from Philadelphia to Pittsburgh, and to 857 (now 65) and 68 from Pittsburgh to Ohio. Now US 1, US 30, 65, and 68.
202 Replaced US 122 (was also 52 from New Jersey to West Chester and 29 from West Chester to Delaware). 202 Renumbered to 702.
6 7 from New York to 5 (now US 19) and 5 from Waterford to 9 (US 20) in Erie. US 6 was later extended west, replacing 77 to the Ohio state line. 6 6 was a 1925 route and was eliminated in favor of US 119/10 and US 219/60.
6N Originally replaced US 6 from Waterford to Erie when US 6 was relocated to extend west to California. Current routing replaced 79 from US 6/US 19 to US 20.
106 19 or 39 (now 652) from New York to US 6, followed US 6 to Carbondale, 47 from US 6 to US 11, followed US 11/2 to New Milford, and 67 from US 11 to US 6. Now 652 east of Indian Orchard, 106 from Carbondale to Kingsley, and 706 from New Milford to Wyalusing. 106 Did not exist before US 106. Replaced US 106 from Kingsley to Carbondale.
206 May or may not have had a state route number. 206 Never assigned.
209 US 6/7 from New York to Milford, 33 from Milford to Clarks Ferry, and 14 from Clarks Ferry to US 22/US 322. 209 Never assigned.
309 Followed US 220/42 from New York to US 6/7, followed US 6/7 from US 220 to 29, was 29 from US 6 to 93, was 93 from Hazleton to US 209/33, followed US 209/33 from Nesquehoning to Lehighton, was 45 from US 209/33 to Palmerton, was route ?? (93? 429?) from Palmerton to Schnecksville, was 29 from Schnecksville to Allentown, was 12 from Allentown to Philadelphia. Now US 220, US 6, and 29 from New York to Bowmans Creek and 309 from Bowmans Creek to Philadelphia. 309 Did not exist before US 309. Replaced US 309 from Bowmans Creek to Philadelphia.
11 2 from New York to Scranton, 39 from Scranton to Selinsgrove, 4 from Selinsgrove to Harrisburg, 41 from Harrisburg to Carlisle, and 33 from Carlisle to Maryland. 11 11 was a 1925 route. Became US 40 in 1926 and also 81 in 1928.
111 4 from New York to Northumberland, and 4 from Harrisburg to Maryland. Now US 15 from New York to Williamsport, I-180 from Williamsport to I-80, 405 from I-80 to 147, 147 from 405 to US 22/US 322, US 22/US 322 to Harrisburg, and I-83 from Harrisburg to Maryland. 111 Never assigned.
611 2 from Scranton to Philadelphia. Now 435 from Scranton to I-380, I-380 from 435 to 611, and 611 from I-380 to Philadelphia. 611 Did not exist before US 611. Replaced US 611 from I-380 to Philadelphia.
711 42 and 64 from New York to Muncy and 4 and 14 from Hughesville to Northumberland. Replaced by US 111. 711 Existed shortly after US 711 vanished but was never renumbered. 711 is the parent route of the x11 family, which consists only of 711 itself.
13 91 from Delaware to Philadelphia and 32 from Philadelphia to Morrisville. 13 13 was a 1925 number. Replaced in 1926-28 by US 422/17 from Philadelphia to Reading, by US 222(/41?) from Reading to Lancaster, by US 230/41 from Lancaster to Harrisburg, and by US 11/33 from Harrisburg to Maryland.
15 Replaced US 240 and was also 34 and 14 from Maryland to Harrisburg, followed US 22/14, US 209/14, and 14 from Harrisburg to Sunbury, replaced US 111/4 from Sunbury to New York. US 15 was later moved to the west side of the Susquehanna River, following US 11 from Harrisburg to Shamokin Dam and replacing 404 from US 11 to US 220, and connecting to its former routing to New York. 15 15 was assigned in 1925, but was renumbered to 115 in 1928 to avoid duplication with US 15.
19 8 from West Virginia to Pittsburgh, 88 from Pittsburgh to Meadville and 5 from Meadville to Erie. 19 19 was a 1925 route. Replaced by US 106 from New York to Scranton, by US 11/39 from Scranton to Selinsgrove, and by US 522/39 west of Selinsgrove.
119 66 from West Virginia Greensburg, 71? from Greensburg to US 22/3, followed US 22/3 to Blairsville, and 10 from US 22 to US 219. 119 Never assigned.
219 60 from Maryland to US 119 and 10 from US 119 to New York. 219 Never assigned.
20 Replaced 9 from New York to Ohio. 20 Never assigned.
120 5 (now US 19) from US 20/9 to US 6/7, followed US 6/7 from US 19/5 to US 219/10, followed US 219/10 from US 6/7 to 55, was 55 from US 219/10 to US 220/64, followed US 220/64, US 111/64, and US 111/4 from 55 to 45, was 45 from US 111/4 to 42, and was 42 from 45 to Reading. 120 Did not exist before US 120. Replaced US 120.
220 42 from New York to 64, 64 from 42 to Mill Hall, 50 from Mill Hall to Bellefonte, and 64 from Bellefonte to Maryland. 220 Never assigned.
22 3 from New Jersey to West Virginia. US 22 later replaced 43 from Harrisburg to Bethlehem and joined US 522/5 from Lewistown to Mount Union.. 22 22 was a 1925 route. Renumbered in 1928 to 29.
122 52 from New Jersey to West Chester and 29 from West Chester to Delaware. 122 Never assigned.
122 45 from Northumberland to 42, 42 from 45 to US 1/12.
222 ?? from Reading to Lancaster and 72 from Reading to Maryland. 222 Did not exist before US 222. Replaced US 222 from I-78 to Allentown.
322 ?? (27?) from Ohio to Meadville, 5 from Meadville to Bald Eagle. US 322 was later relocated to follow 250 from US 220/64 to 53, 53 from 250 to 5, 5 from 53 to US 22/3, followed US 22/3 from 5 to Harrisburg, 5 from Harrisburg to West Chester, followed US 202/29 from West Chester to US 1/12, followed US 1/12 from US 202/29 to 61, and replaced 61 from US 1/12 to New Jersey. 322 Never assigned.
422 217 from Ohio to New Castle, 17 from New Castle to US 22, and 17 from Reading to Philadelphia. US 422 was later extended along US 22 from Reading to Harrisburg. 422 Never assigned.
522 39 from US 11/4 to US 22/3, followed US 22 from Lewistown to Mount Union, and replaced ?? from Mount Union to Maryland. 522 Never assigned.
622 Possibly replaced part of 19 or 39 and 928 from Mount Union to Maryland. 622 Never assigned.
224 Replaced 317 from New Castle to Ohio. 224 Renumbered to 624.
30 ?? (5?) from New Jersey to US 1, 1 from US 1 to Pittsburgh, followed US 22/3 from Pittsburgh to Imperial, and replaced ?? from Imperial to West Virginia. 30 Never assigned.
230 41 from Harrisburg to Lancaster. Now 230 and 283. 230 Did not exist before US 230. Replaced US 230.
40 81 from Maryland to West Virginia. 40 Never assigned.
140 Replaced ?? (14?) from Gettysburg to Maryland. 140 Never assigned.
240 Replaced 1925 route 24 from Maryland to Harrisburg and became US 15 before 1928.. 240 Appeared after US 240 disappeared. There was never a need to renumber 240.
46 Replaced 987 from US 611 to New Jersey. 46 Never renumbered.
62 65 from Ohio to US 322/5, followed 8 from Mercer to Oil City, replaced ?? from Oil City to Tionesta, and was 66 from Tionesta to New York. 62 Renumbered to 100.


State and US Highways in 1928

Below is a map showing the state route designations that were assigned to the US highways in 1928. Some US routes (e.g., US 62 and US 202) were assigned later and are not present on this map; others have been relocated since 1928 and will appear very differently on a modern map. On segments where the state route designation is uncertain, an educated guess is made and indicated with a gray route marker. There were far more state routes designated in 1928 than this map shows. Only a select few state routes are shown besides those running concurrently with the US highways.

Pennsylvania's US Highways and Their State Highway Designations in 1928 (Click to enlarge, 390 KB)
Map by Timothy Reichard



Three-Digit Parent Routes

Several one- and two-digit state route numbers were forbidden for assignment in the 1928 system because they matched US highway numbers. However, in several cases, parent and child routes were still assigned matching these numbers. Such parent routes were given the lowest three-digit number within the family that was greater than the highest US route number in the same family. For example, US 15 and no other US x15 routes were in the state, so 115 became a parent route instead of 15. In the case of the x11 family, US 611 had been assigned, so the appropriate parent route for a PA x11 family is the next highest x11, 711. All of these parent routes except 1 still exist.

Forbidden Route Parent Route Remarks
1 1 1 was allowed as a state route, probably because almost its entire route followed a US highway (US 1 and US 30), and thus 1 could be decommissioned without any problem.
6 None There was no x06 family. The parent route would have been 306, since US 6, US 106, and US 206 already existed.
11 711 US x11 numbers were assigned as high as US 611, so 711 was free as a parent route.
13 113 113 became the parent route for the extended x13 family, which includes 213-713 and even 813. No US x13 routes existed in the state besides US 13.
15 115 115 replaced 1925 route 15 as the parent route for child routes 215-715. No US x15 routes existed in the state besides US 15.
19 None There was no x19 family, though a few x19 routes (319, 519, and 819, all running north-south) appeared along US 19 and US 119. The parent route would have been 319 if it had been initially assigned, since US 19, US 119, and US 219 already existed.
20 320 Since US 20, US 120, and US 220 existed in the state, the x20 family began with parent route 320 and included child routes 420 and 520.
22 None There was no x22 family, though 722 (running east-west) appeared later along US 222 near Lancaster. 722 was the only x22 number not already assigned and would have been the x22 parent route if it had been initially assigned.
30 None There was no x30 family. If there had been an x30 family, the parent route would have been 330, since US 30 and US 230 existed in the state.
40 340 340 is the parent route and lone member of the x40 family. Numbers 40, 140, and 240 were assigned to US highways.


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