Credit: Danya Henninger / Billy Penn

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Each day, hundreds of SEPTA buses run through the city and surrounding suburbs. Down Broad, across Cecil B. Moore or diagonally along Germantown Avenue, the city’s 125 bus routes make up Philly’s most robust public transit option, by far.

Philadelphians who ride them come to identify with their daily line — be it the 2 to Hunting Park or the 48 to Brewerytown.

How’d those routes get numbered in the first place?

At first glance, there doesn’t appear to be rhyme or reason to the numbers and letters assigned to Philly’s buses. Even SEPTA officials asked by Billy Penn weren’t quite sure how these labels were assigned.

A trip to the city archives revealed the answer. Many of the route names were passed down from the transit system that preceded SEPTA — a late-1800s agency that began in an era when public transit was horse drawn.

That is the origin of the bus route names we know today, even though the system itself has been revamped many times.

There might be more change coming soon, as the entire SEPTA bus network undergoes a redesign intended to improve service. The transit authority is considering changes like all-door boarding and elimination of transfer fees. In the redesign process, the authority told the Inquirer, there’s even the possibility that existing routes could disappear.

But even with the new design, most of those age-old numbers and letters will likely stay the same.

A horse-drawn streetcar shown at 6th and Jackson Street in 1894 Credit: Library Company of Philadelphia

City gives up holding its horses

It all started in the late 1800s, when officials at the Philadelphia Traction Company — that’s what our public transit agency was called back then — started insisting the city upgrade its fleet to modern trolley cars.

PTC cofounder Peter Widener wrote a letter to then-Mayor Edwin Stuart basically begging him to authorize a switch from the mechanism they used at the time…literal horse-drawn street cars. Philly were among the last cities in the United States to hold onto horse power as a means of public transit, and Widener was getting fed up.

“There is today absolutely no choice between horse-cars and trolley cars,” Widener wrote in 1892. “And no reasonable prospect of anything better in the near future.”

Happily for the transit commissioner, the mayor agreed. Together they authorized constructing trolley tracks on a handful of streets, including 12th, 15th, 20th, Sansom, Pine, Christian and Morris.

PTC conducted several studies to determine ridership needs, and over the course of the next few decades, mapped dozens of trolley routes all over Philly and the ‘burbs.

It seems the transit agency numbered the routes chronologically, demonstrated in a March 1929 transit report that lists them in order of their creation.

  • Route 2, Broad and Pollock to 13th and Erie
  • Route 3,  Frankford and Bridge to 13th and Filbert
  • Route 4, 2nd and Erie to 7th and Ritner
  • Route 5, Frankford and Bridge to 2nd and Bridge

Later additions included Route 39, carrying passengers from 33rd and Dauphin to Cumberland and Richmond, and the suburban Route 77, from Chester to Media.

Actual motor buses didn’t enter the system until 1923, records show, and to differentiate from the trolleys, they were lettered instead of numbered — from Route A through Route X-1.

The biggest difference from the 1920s-era system, naturally, is the fare. Back then, it cost a mere 13 cents to ride the bus.

In the 1920s, there was a mass eradication of trolley routes. Mayor J. Hampton Moore signed dozens of ordinances to rip up tracks all over the city, from Emerald Street to Passyunk Avenue. Many of the fallen electric routes were converted into buses — and they maintained their existing numbers.

Credit: Michaela Winberg / Billy Penn

Under 90 = city; over 90 = suburbs

Some of these old routes have been carried into the modern era. Route 5 rode Kensington Avenue, the 15 traversed Girard Avenue and the 43 saw the length of Spring Garden Street, just like they do today.

But not all of them have survived 100+ years. Over the course of the last century, countless transit routes were retired, and along with them went their numbers.

Since then, SEPTA has taken the reins and slowly reassigned those old numbers. Not with any particular intention, except that city routes are numbered under 90, and those in the ‘burbs are higher than 90. Also, per spokesperson John Golden, the authority generally waits a few decades after a route is retired to put the number back into use.

Prime example: Route 49 was able to pick up that number when it was created two years ago because the moniker hadn’t been used since the 1980s.

“Over time most numbers have been used,” said Golden. “But numbers are reused after a reasonable period of time that wouldn’t cause confusion.”

As SEPTA continues its bus redesign, the transit authority is hoping to stray away from lettered bus routes and more toward numbered routes, Golden said. During the shakeup, there’s the potential for others to change, too.

Golden wasn’t about to make predictions about which ones. “Designations will be evaluated as changes are proposed,” he said.

Michaela Winberg is a general assignment reporter at Billy Penn. She covers LGBTQ people and culture, public spaces, and transportation and mobility. She also sometimes produces radio and web features...