Peculiar Pittsburgh

Why Downtown Pittsburgh’s numbered streets and avenues don’t line up

Sixth Avenue becomes Seventh Street. It’s confusing. But it’s also quirky.

1872 map of Pittsburgh

1872 map of Pittsburgh

courtesy of Pittsburgh City Archives
MJ Slaby

Pittsburgh’s Downtown streets aren’t easy to navigate — Sixth Avenue turns into Seventh Street and Seventh Avenue just ends at Liberty.

“Nothing [Downtown] quite connects the way that it should. You have to do a jog when it seems you could go straight,” said Derek Dauphin, a senior planner for the city. “Pittsburgh is one of those rare cities on a confluence.”

That gives Pittsburgh some character and quirks not found in other cities, he said. But it can also cause confusion, especially for tourists and for those driving them around like Brian May, a captain for Just Ducky Tours.

“I have to admit that driving an oversized vehicle through the narrow streets of Downtown is a little bit ‘quacky,’ but it’s the ‘nature of the beast’ … Downtown traffic patterns lend themselves to constant entertainment for all to enjoy (endure),” he told The Incline via email.

Quack. Quack. Quack.

That inspired May to ask The Incline’s Peculiar Pittsburgh:

“Why does Sixth Avenue take me toward the Seventh Street Bridge and Seventh Avenue takes me toward the Ninth Street Bridge?”

We’ve received dozens of Peculiar Pittsburgh questions, but The Incline’s staff really loved this question — and a few others about Downtown oddities — so we had readers vote on the first question they wanted us to investigate.

More than 500 people voted, and though this question placed second, we decided it was a query worth answering. Read the first place question and its answer here. And don’t worry, if we didn’t answer your question yet, there’s still hope, and there’s still time to ask a new question.

A historical grid

“The answer to the question is simple. Two street grids intersect at Liberty Avenue. One grid is parallel to the Monongahela River. The other grid is parallel to the Allegheny River,” Don Carter, director of the Remaking Cities Institute at Carnegie Mellon University, told The Incline in an email.

Liberty Avenue divides the two grids, creating the odd matchups of numbered avenues and numbered streets, added Michael Glass, an urban geographer at the University of Pittsburgh.

The grids have largely been in place since the late 1700s, when they were laid out by Col. George Woods and his assistant, Thomas Vickroy, according “Pittsburgh: The Story of An American City,” a book recommended by Carter.

Woods and Vickroy — yes, Wood and Vickroy streets are named for them — used a previous plan created by Col. John Campbell in the 1760s after houses near Fort Pitt were destroyed in preparation for an attack by Native Americans, per the book. Woods and Vickroy expanded that layout and added Penn and Liberty avenues.

But at that point, the streets in the Monogahela grid were numbered streets and the ones in the Allegheny grid were named streets, Carter and Pittsburgh Archivist Nick Hartley pointed out.

Take a look at this 1835 map:

1835 map of Pittsburgh

1835 map of Pittsburgh

courtesy of Pittsburgh City Archives

Until the 1860s, Pittsburgh was triangle-shaped with boundaries from the current David L. Lawrence Convention Center to the Allegheny County Jail, Hartley said. But in 1868, Pittsburgh annexed the townships of Pitt, Peebles, Liberty, Collins and Oakland.

That prompted changes in street names.

“It seems that one of the solutions to connecting the annexed territory was to number the streets along the Allegheny River into Lawrenceville and beyond. These name changes were made less than two months after the first round of annexations in 1868. More would follow in 1872, and the rest is history,” Hartley said in an email.

And at some point the numbered streets turned to avenues.

Check out this 1872 map:

1872 map of Pittsburgh

1872 map of Pittsburgh

courtesy of Pittsburgh City Archives

One oddity that still exists is Fifth Avenue, which doesn’t end at or before Liberty Avenue like the other avenues, but crosses it and turns into Cecil Place at Penn Avenue.

Cecil Place was one of the busiest streets Downtown in the early 1900s, but was only 20 feet wide, creating problems for trolleys turning onto the street, according to Hartley.

“Cecil was finally widened to 50 feet in 1907, and Fifth Ave. was extended one block the following year. Unfortunately we can’t say definitively why Fifth Ave. absorbed a block from Cecil, but we’re guessing it had to do with the definitions of alleys, streets and avenues that prevailed at the time,” Hartley wrote to The Incline.

Two grids today

Merged grids aren’t that uncommon, Dauphin said. But what makes Pittsburgh peculiar is that it is bordered by two rivers instead of just one.

As reader May pointed out, not only is it confusing in general, but Pittsburgh’s streets can be even more troublesome when there are street and bridge closures due to events, sports, parades and more.

So why stick with this two-grid system?

Renaming the streets wouldn’t be easy, Glass pointed out. Not only would the streets need to change, but so would buildings and street addresses. Plus it would be expensive.

He said signage would be a better solution than renaming, which doesn’t always stick. Here’s looking at you, Avenue of the Americas.

Physically changing the streets would also be expensive and require a lot of demolition, something planners are trying to avoid, Dauphin added.

Plus, while it can be a transportation issue, it’s not *all* the grids’ fault.

When it comes to street closings and navigation, the shape of Downtown is a factor, but so are one-way streets, bus lanes and sidewalk bump outs, said Pittsburgh Police Cmdr. Ed Trapp. He advised using public transit and learning multiple ways to get around in case your usual path is blocked.

Above all else, city planning experts interviewed by The Incline said the two grids are quirks to be embraced.

The layout allows for branding of specific areas Downtown such as the Cultural District or Market Square, Glass said.

Plus, if someone is on Smithfield or Wood streets, they can look north and see the buildings on other streets, Dauphin added. It’s a natural way-finding system that wouldn’t be possible with a typical grid.

The merger allows for Liberty Avenue to be unique through the different uses of triangle-shaped space, he said. There are triangle-shaped buildings like Wood Street Galleries, triangle-shaped plazas like at the KNL Gates building, and PNC Triangle Park.

In some ways, the two grids are a benefit to the Golden Triangle, Dauphin said. “It’s the occurrences of history that make cities interesting.”