Downtown Pittsburgh has a perfectly good reason to be running out of room for more cars: its streets have been there since 1784.

"In Pittsburgh, we have too many cars chasing too few parking spaces," Merrill Stabile, president of the city’s largest parking operator, said last week. ?I am in favor of building a few more parking garages. But we?ll never be able to build enough to meet the demand, in my opinion, if we continue to grow like we?ve been growing.?

That’s why Stabile said he’s among the Pittsburgh business leaders backing a plan, announced today, to reduce downtown’s dependence on car traffic by adding a protected bike lane to Penn Avenue.

Jeremy Waldrup, CEO of the Pittsburgh Downtown Partnership, said the protected lane, which will return Penn Avenue to a one-way street by removing an eastbound traffic lane, will make it comfortable for most people, not just the bold few, to bike downtown.

"One of the most important things is that we have as a city developed this incredible trail system, many of them leading to downtown," Waldrup said. ?But once you?ve made it to the borders of downtown, you?re literally on your own to get into the city.?

Penn Avenue’s new one-mile bidirectional bike lane, being installed over the next few weeks with a total planning and construction budget of $73,000, will be one of the first protected lane projects in any American central business district.

And it’s happening one of the country’s oldest downtowns: a triangular grid built for horses and carriages that by 1900 had become the 11th-largest city in the United States — and has spent the century since then trying to find room for cars.

"The Penn Avenue corridor that we’re looking at is kind of in the heart of our cultural district," Waldrup said. "Tens of thousands of people come into this area for culture."

Will Bernstein, who commutes daily into downtown Pittsburgh, agreed.

"You have the symphony, the opera more or less, you have a bunch of new restaurants," said Bernstein. "Convenience stores and stuff. There’s actually a nice little park where they do concerts in the summers."

Like Stabile and Waldrup, Bernstein thinks the Penn Avenue bike lane will make it easy for families and casual riders to get downtown by trail and then venture into the retail core for entertainment, food and shopping.

"For people who mostly just ride on trails, if they’re riding the river trail and want to get into downtown from the point, Penn Avenue is kind of the natural route," he said. "If people want to have lunch, there’s an ice cream shop, you know, stuff like that."

Protected bike lanes are part of the next step in Pittsburgh’s recovery from rust-belt collapse, Allegheny County Executive Rich Fitzgerald said.

"We have a growing city after 25 years of managing decline," Fitzgerald said. "We?re now trying to figure out how to manage growth in a concentrated downtown area in which cars just can’t handle the load anymore."

Penn is one of three protected bike lanes announced this summer by Pittsburgh Mayor Bill Peduto, who joined Fitzgerald and others for a Green Lane Project study tour to Denmark in June to see how protected bike lanes and other low-stress infrastructure have helped Copenhagen built a thriving and egalitarian economy without relying on ever-increasing car traffic.

Another of Peduto’s first three projects, a quarter-mile trail link on Saline Street in the Oakland area, was striped last week and lined with vertical posts on Tuesday, becoming the city’s first protected lane. The third is just north of it, on Schenley Drive and Panther Hollow Road.

"On the East Coast, you know, we had cities that were built before the automobile and then we adapted them to be primarily used for the automobile," Peduto said in an interview. "And now we’re in that next phase, and we’re trying to figure out how all modes of transportation can work in a system."