When traveling about in city neighborhoods, you may think you know where you are, but you could be wrong.
Even longtime residents have been surprised to find out they don't live where they thought they did, at least officially.
Historically, neighborhoods followed ward boundaries. But in the post-industrial era, the birth and re-shaping of neighborhoods usually happens thanks, or no thanks, to the city Planning Department.
It becomes more apparent during a vibrancy phase.
When Mayor Bob O'Connor declared Downtown the city's 89th neighborhood, it sounded like a great thing for Golden Triangle residents. But if they aren't already, they'll probably soon be arguing over where the Strip and Uptown really start.
Not long from now, some people in parts of Oakland, Shadyside and East Liberty may start waking up in a new neighborhood called Baum-Centre.
Planning officials couldn't be reached for comment, but the department has been developing a strategy for the area's identity with stakeholders for several years. It calls Baum-Centre "a unique urban district in a state of transition," with "the potential to be a real place."
That sounds like the definition of neighborhood. It would stretch from Craig Street in Oakland to Penn Avenue in East Liberty and include the Hillman Cancer Center, which now is in a tiny notch of Shadyside that would be Bloomfield if the line were straight, "but it doesn't look like Bloomfield right there and it doesn't look like Shadyside," said Franklin Toker, an historian who wrote "Pittsburgh: An Urban Portrait." "It's more in keeping with the scale of East Liberty."
Over the years, the city has made up new names for places, but residents don't always go along.
Many people still refer to living in Soho when they are between West Oakland and Downtown, say at Fifth Avenue at Jumonville Street. The street signs at the intersection tell you that you are in the Bluff. Decorative signs hanging along street poles say you are Uptown.
So, Soho has three names, depending on your preference.
Kenneth Stiles of the Friendship Preservation Group, said he remembers looking at some old planning maps in the 1970s, when he lived in what was then the East Liberty census tract, seeing a little notch labeled "Friendship" and realizing that "a planner had renamed my neighborhood."
When Friendship Preservation and its sister organization, Friendship Development Associates, formed in the 1990s, he said, "we defined our boundaries. We didn't ask anyone what we could be."
The neighborhood is Negley Avenue to Gross Street and Penn to Liberty or Baum, depending on which street is the southernmost.
"It had to do with the architecture," he said, "but it created an endless war with the people in Bloomfield."
"What I often do is ask people, 'Where do you think you are?' " said Mr. Toker. "When the first edition came out, I got a call: 'You put me in Perry Hilltop,' " he said, imitating the caller's high-pitched, angry voice. "I said, 'Where do you think you are?' and he said, 'Observatory Hill.' "
The city does not recognize Observatory Hill as an official neighborhood, but street signs down in the valley on the other side of Interstate 279 tell you that you are in Observatory Hill.
A neighborhood has to end and begin somewhere, but it can get confusing.
"I quoted a woman at a community advocacy meeting in East Allegheny saying, 'What's this Deutschtown?' " Mr. Toker said. "The woman, who lived in Deutschtown, continued, 'I have never moved in my entire life and I've never heard of it.' "
Deutschtown is a self-styled part of East Allegheny, which is part of the North Side, which is not a neighborhood per se. North Side, like the East End, is full of large and small, desirable and undesirable neighborhoods, some of which are not official.
Neither Schenley Farms nor Schenley Heights is a neighborhood according to the city, but people in Schenley Farms and Schenley Heights disagree.
The same is true of Park Place. The city does not officially recognize it, but there are signs that say "Welcome to Park Place" that the city once installed in what it now considers to be Point Breeze.
Numerous neighborhoods look across a major thoroughfare at each other. It's easier to feel the divide when the street is as wide as Fifth Avenue and the business corridors are elsewhere, such as Shadyside's and Squirrel Hill's. Similarly, West Liberty Avenue separates Beechview and Brookline.
But when you are on the sidewalk north of Penn Avenue at Winebiddle Street, you are in Garfield looking across the street at Bloomfield. Farther east, Garfield looks across at Friendship.
"If you go back in time, city wards were as much an important division within the city as was neighborhood," said Chris Briem at the School of Urban and Social Research at the University of Pittsburgh. "A lot of neighborhood boundaries match the ward boundaries to this day."
One vestige of that is the 31st Ward, whose resident advocates identify as such, as the city once did. It includes part of Lincoln Place and Hays.
"The sociological question is why people start to refer to one section of a neighborhood differently," said Mr. Briem.
Some neighborhoods that existed in the 1950s have vanished altogether, such as Harper Hilltop in the North Side and Ridgemont-Chicken Hill, behind Mount Washington. Others that still exist showed up in different formations, such as East Brookline-Overbrook and East Northside.
Renaming a place doesn't sway the most stalwart residents, but it might be counterintuitive, said Mr. Toker, who refers to "the beat of the neighborhood" as the best guide.
"Surely planning is going to work better if you know how that neighborhood sees itself," he said.
Diana Nelson Jones can be reached at firstname.lastname@example.org or 412-263-1626.