Near downtown Pittsburgh, along the 10th Street Bypass and Allegheny riverfront trail, large metal rings that look like giant doorknockers are fixed to retaining walls. They’re rusty and discolored after decades of enduring the city’s weather.

Good Question! listener Stewart Williams noticed these rings while bicycling around the city.

“I’m not entirely sure what they’re there for,” Williams said. “I’m wondering if they’re for decorative purposes or if they actually have a purpose at all.”

Williams noticed two different sets of rings; a series of giant ones attached to columns along the Allegheny River near the Point, and trios of smaller ones lining the 10th Street Bypass retaining wall. The rings on the columns are much larger than those on the bypass, which are positioned in metal brackets along the wall.

Both sets of rings are traces of the area’s past as a commercial wharf, according to Pittsburgh history buff Tim Killmeyer. The rivers were one of the main reasons the city developed, he said, so it made sense that the riverbanks were bustling spaces. The Pennsylvania canal ran through the city carrying goods, and shipbuilding was a major industry in the city’s earliest days. The Allegheny Wharf was primarily a hub for industrial traffic, while the Monongahela Wharf was used for commerce and social gatherings.

“Just like everybody would go to Point State Park today, everybody went to the Mon Wharf to celebrate Pittsburgh stuff,” Killmeyer said.

In the early 1900s, Pittsburgh’s population nearly doubled to more than 500,000. On both wharfs, there was no barrier between the water and the land, like a beach. Steelworks, brickyards and machine shops lined the rivers, and barge and freight ships docked nearby to transport products. The bridges on the Allegheny River — 6th, 7th, 9th, 16th, 31st and 40th — had recently been raised, allowing steamboats and additional river traffic to reach the Allegheny Wharf.

As automobiles gained popularity, drivers would use the wharfs are parking lots. Between the industrial activity, the nearby elevated Pennsylvania Railroad line, and the dense rows of cars, space was running out on the Allegheny Wharf. Developers needed to find a way to route traffic around downtown and decided to build a bypass on the wharf.

Construction began on what was then known as the Duquesne Way project, a route parallel to the rail lines leading from the Point to the Strip District. But a persistent issue challenged the builders: flooding. Duquesne Way was frequently inundated by the rising Allegheny River. So as workers finished what would become the 10th Street Bypass, barges or passing boats would tie to the rings on the bypass’ retaining wall to keep from drifting away.

“You would bring your boat in and push them against the wall out of the middle of the rapid channel and move them out of the way until the river started to recede,” Killmeyer said.

The 10th Street Bypass, along with most low-level roadways near the river, still flood, but improvements to the region’s lock and dam system have mitigated much of the problem.

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

After the Duquesne Way project —now called the 10th Street Bypass — was complete, the rings were no longer necessary. They’ve been a lot harder to access since the Allegheny Riverfront Trail was built between the bypass and the river in the late 1990s. That trail is where several larger rings hang from support columns. People walking along the river are often seen jumping to reach them. Those rings were installed when the wharfs were still bustling, according to Gateway Clipper fleet owner Terry Wirginis. He remembers his grandparents used similar rings along the Monongahela River during high water conditions

“Sometimes, like during Hurricane Agnes in 1972, the water came almost all the way up to the surface of the parkway,” Wirginis said. “So we were tied to those rings.”

But he said the rings are rarely used anymore. They were never part of a lock and dam system, as some have speculated. Ultimately, they’re a reminder of the region’s rich history of river commerce.

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