With more than 150,000 photos taken over 120 years, the Pittsburgh City Photographer collection is a historic record of a changing and developing city.

But when the city’s law department filed an assignment to photograph a sidewalk before a construction project, history was not on anyone’s mind. The city simply wanted a record so it wouldn’t lose a lawsuit.

“I don’t think anyone really ever thought at the time, ‘We’re documenting the city for posterity.’ It was just all inadvertent,” said Frank Kurtik, a photo archivist who began organizing the collection in 1981. “There’s quite a beauty to that.”

Held by the Archives & Special Collections at the University of Pittsburgh, the collection preserves photos and negatives created from 1890 to 2002 and hosts almost 15,000 images in a searchable online database. Most of the photos were captured by photographers working for the city’s Division of Photography, which received assignments from various departments.

Though the city still has a photographer, their job is essentially that of a police photographer. The city photographer position as it existed since 1907 was eliminated in 1971.

When Pitt hired Mr. Kurtik, the collection was in bad shape. The negatives were in crumbling envelopes, Mr. Kurtik said. His first task was to ensure the artifacts were properly stored and preserved. But he immediately recognized the collection’s importance.

“It was so significant in capturing the way the city looked over much of the 20th century, I immediately [let] people know I was working on the collection,” he said. “Word got around to scholars, students and the general public.”

As Pittsburgh continues a decades-long transition from being an industrial city, the Post-Gazette set out to see how different the city looks today compared to the early- and mid-20th century. Standing where the city photographer stood, we captured the same scene — some are hardly recognizable, others look almost the same. And behind each photo is a history of Pittsburgh’s neighborhoods, people and culture.

Clarification, posted Jan. 2, 2019: The University of Pittsburgh's Archive Services Center is now known as Archives & Special Collections. The text has been updated to reflect this change.