Topography And Annexation Shaped Mismatched Pittsburgh Streets

Jul 17, 2018

It's easy to get lost navigating Pittsburgh. Cars ascend and descend sloped roads at angles and maneuver countless one-ways and alleys. Because much of the city is arranged in this disjointed manner, moving through neighborhoods can feel emblematic of the Steel City.  

Good Question! listener David Braman found this to be particularly true in Oakland. Walking along Fifth Avenue, he noticed the perpendicular streets to the main stretch didn’t line up.

A historic plat of West Oakland from Sutherland Drive to Fifth Avenue. Darragh and Lothrop streets (formerly Lothrop Avenue) can be seen intersecting with Fifth Avenue at the bottom of the map, but not connecting at a straight, 90 degree angle with the section of street on the other side of Fifth.
Credit Katie Blackley / 90.5 WESA

“It really makes it very convoluted just to walk across the street,” he said.

He’s referring to Darragh and Lothrop streets. Both connect to Fifth Avenue and rise at a 12 percent grade. They weave east by UPMC Montefiore and medical speciality buildings, and neither of them come to a perfectly square intersection with the streets on the other side of Fifth Avenue.

“It’s almost as if there were a fault line that got knocked askew,” Braman said.

Pittsburgh's peculiar patterns

This "askew" alignment has to do with the terrain and eventual annexation, according to policy analyst Chris Sandvig with the Pittsburgh Community Reinvestment Group. The city's roads make up a “colliding grid system,” unlike the traditional model of urban grid design.


Most people imagine grid systems as engineered parallel streets intersecting at 90-degree angles. They look easy to navigate and predictable, as if they were planned with purpose and clarity. That's not often the case in Pittsburgh. City streets resemble a puzzle, because each neighborhood used to support its own town or borough.

Each street in the city of Pittsburgh has a file that details its history, including any ownership and name changes.
Credit Katie Blackley / 90.5 WESA


“It’s a combination of municipalities being gobbled up by the city as it was growing in the 1800s and topography,” Sandvig said.


Oakland’s intersections along Fifth Avenue are offset because they’re built into hills. They can’t sustain the grid shape as they wind upward. Instead, they shift to match the slope. This happens all over Pittsburgh, with roads adjusting their alignment to fit into the terrain. A recent Pittsburgh Reddit post went into this idea, graphing the street grid on a compass.


Topography, after all, contributes to the city's highway structure, neighborhood boundaries, transit systems and those wacky city steps


Pittsburgh’s communities were hyper-locally designed, so this kind of configuration occurs in other neighborhoods, too. The Golden Triangle downtown, for example, is situated on two grid systems that align with the converging waterfronts, ending near the Point. Parallel roads from Fort Pitt Boulevard to Seventh Avenue join Stanwix and Ross streets perpendicularly to form the Monongahela River grid system. Along the Allegheny River, Fort Duquesne Boulevard to Liberty form square intersections with the streets from Commonwealth Place to 11th Street.


A screenshot of the city of Pittsburgh, showing the various grid-like systems in what used to be separate towns and boroughs. The South Side Flats, for example, was once called Birmingham and East Birmingham. It was annexed by the city of Pittsburgh in 1872.
Credit Google Maps

Annexation, the act of adding towns and boroughs to an existing territory, affected the navigability of Pittsburgh. Between the 1860s and 1950s as the city’s physical boundaries grew, its population reached a peak of more than 600,000 residents.

Rethinking urban design

At the turn of the 20th century, a new architectural trend called the City Beautiful movement made its way to Pittsburgh. Its philosophy helped shape neighborhoods, especially Oakland.

The 42-story Cathedral of Learning in Oakland is a beacon of the neighborhood. The green space and sprawling acres of parks weaved throughout the area are reminiscent of an architecture trend at the turn of the 20th century emphasizing a separation between dense urban life and "harmonious" spaces.
Credit Katie Blackley / 90.5 WESA

“The city beautiful movement was a lot about more open space and more meandering-looking things, aesthetics,” Sandvig said.

Architects wanted to create civic centers in cities, where people could get away from crowded, polluted downtowns. Oakland Business Improvement District executive director Georgia Petropolous grew up in the neighborhood and said it always felt like the community embraced the tenets of the movement.

“You had your parks, you had your areas of green, you got away from smog and pollution, you had your museums, you had your library,” Petropolous said.

Oakland has tiny apartments crammed with students and mammoth mansions built by Pittsburgh’s great industrialists. The neighborhood also has dense towering medical facilities and universities that bump up against acres of sprawling parks.

This is part of our Good Question! series where we investigate what you've always wondered about Pittsburgh, its people and its culture.

“The beautiful Schenley Plaza, Phipps Conservatory, even the land the Cathedral of Learning is on and the William Pitt Union are on, still have remnants of that green movement as a place for escaping,” Petropolous said.

From its modest beginnings as farmland, Oakland has grown to become the third largest employment center in the state. Over time, its infrastructure adjusted to meet those needs. The “city within a city,” as Petropolous said many call it, was an essential characteristic of the neighborhood when Pittsburgh as a whole needed to switch its major industry from manufacturing to higher education and medicine.

“It’s the heart of Pittsburgh’s transformation,” Petropolous said.