Stacy Innerst, Post-Gazette Click illustration for larger version. Listen in Take a ride into trouble with map maker/highway interchange expert Bob Firth and the PG's Cristina Rouvalis: The merge from the West End Bridge to 65 South to 279 North (Northshore Expressway) The Boulevard of the Allies onramp to the Parkway East outbound The West End Circle Firth explains the factors that make for a scary merge Online graphic See a map of worst road merges, according to Post-Gazette readers

You don't have to drive far in Pittsburgh to stare down a scary road merge -- the kind that makes ordinarily confident drivers hold their breath, floor it and pray.

But which is the most menacing merge of all, the one so dreaded that drivers go miles out of their way to avoid it?

It's hard to narrow it to just one merge -- the Parkway alone has many worthy candidates -- but our readers put one of them in a category all by itself: the Squirrel Hill on-ramp to the Parkway East outbound.

That torturous example of traffic-engineering-turned-sadism was the winner among readers who e-mailed us, one of three criteria the Post-Gazette used to identify the scariest merge in the Pittsburgh region in our highly unscientific way.

The informal reader survey was overwhelming -- 39 votes, compared with eight for the closest competitor, the Carnegie on-ramp to the Parkway West toward the airport.

Don't be fooled by the Squirrel Hill ramp's peaceful approach through a tree-lined residential street. It's like the slow chug on a roller coaster before the stomach-churning dip. To enter the highway, you must accelerate from a dead stop into speeding traffic, all the while dodging cars exiting the highway on the same lane. Merge over another lane immediately, lest you find yourself back on local streets and have to repeat the fun again.

Just how bad is this merge at the mouth of the Squirrel Hill Tunnel? Consider these reader reviews:

"What mad, possibly opium-fueled dreams the PennDOT designer who came up with this doozy was having I know not, but I do know that the intersection would be worthy of an Escher painting," says former PAT bus driver Jamie Fritz of Penn Hills.

Ms. Fritz, 45, even drives out-of-towners to the merge so they can experience a "thrill ride" less expensive than the ones at Kennywood.

"Just blow up this area and start again," says Carlene M. Yurko, a 36-year-old paralegal from Squirrel Hill.

"Warning: No automobile under 100 horsepower should ever attempt to enter Death Row," says Dan Simon, a 47-year-old from Squirrel Hill who gladly traded his stick-shift Suzuki Sidekick for a more powerful Honda CR-V.

Some merges rattle drivers so much they ache from sheer dread.

Rachel Slifko gets a pit in her stomach and feels limp after she has to merge from the Parkway West inbound over to 51 South Uniontown, before the Fort Pitt Tunnel. The 60-year-old woman from Dravosburg has to cut quickly over two lanes while other motorists flying down Banksville Road cross those lanes in the opposite direction.

"It's homicide waiting to happen," she says.

Shannon King clenches her teeth so tightly that her mouth is sore by the time she makes her way past the merge at 279 North and the Perrysville on-ramp. It doesn't matter that the 25-year-old driver from Ross is on 279 and other motorists have to merge into her lane. "It is a high-speed traffic sandwich," she says.

The 131 reviews from readers weren't the only criterion for singling out dreaded merges. Among those merges nominated by readers and a road expert, we looked at the rate of accidents between 2001-05 that either caused injury or rendered a vehicle unfit to drive.

The Fort Pitt Bridge outbound had the most -- 50 accidents or an average of 10 per year. Second was the stretch of road sometimes called the Northshore Expressway -- connecting the West End Bridge to 65 South to 279 North. That blind merge had 37 accidents during the five-year period.

Surprisingly, the Squirrel Hill exit so dreaded by our readers had significantly fewer accidents -- 14 over five years. "It is an urban annoyance and does cause congestion," says Todd Kravits, PennDOT district traffic engineer. "Surprisingly, it has a very low accident rate."

A third way to size up merges is to ask an expert. So we enlisted map maker Bob Firth, president of Informing Design Inc. in Pittsburgh, to valiantly drive his Toyota Camry through some of the worst merges around town.

For the record, Mr. Firth is a fearless driver, an intrepid merger, a road warrior who has spent so much time studying highway interchanges that he has developed color-coded maps for Pittsburgh sold at www.BigBurgh.com. He shrugs off the Squirrel Hill on-ramp onto Parkway East as no big deal.

"It has a stop sign," he says, removing the suspense factor for him.

But even he has his limits.

He was driving across the West End Bridge onto Route 65 South at the merge point with 279 North. Suddenly, a black van, whizzing by on the right from the Fort Duquesne Bridge and hidden from view by a Jersey barrier, appeared next to him as his lane narrowed to nothing. Mr. Firth swerved slightly to the left to avoid a crash -- somehow steering clear of another barrier.

"Ohhh, that is bad. That is really bad," Mr. Firth said. "That was completely blind. The guy was coming around the bend very fast. It is an asphalt no-man's land."

That Northshore Expressway topped Mr. Firth's list of scary merges. Another blind merge he tries to avoid: the Boulevard of the Allies on-ramp to the Parkway East outbound. He is also wary of the on-ramp from Braddock Avenue south onto the Parkway East inbound. It is a double merge separated with a concrete barrier from the other Edgewood merge lane. He has had near-misses there at night because it's hard to tell whether the car lights are on the Parkway or if they are on the other merge lane.

Mr. Firth says he gets a crick in his neck from the re-configured merge from Liberty Avenue onto the Fort Pitt Bridge -- a dead stop that requires drivers to turn about 120 degrees so they can see traffic flying by off the Fort Duquesne Bridge.

"You need a portable chiropractor."

He thinks Pittsburgh merges, tricky because of our hills and bridges, are worse than the merges in most cities and up there with the ghastly merges in New York City.

People confronting a bad merge sometimes curse some long-dead or retired traffic engineers, whose names mercifully are not plastered on the merge points.

Joe Monteleone, 58, has seen cars rear end each other at the merge from the West End Bridge to 279 North, a merge he takes often to get to his home in Fox Chapel. "The person at PennDOT who designed this little gem deserves to merge on it every five minutes through eternity! No, that's way too harsh..."

But PennDOT says it's not fair to second-guess engineers who designed roads in the 1950s, back when federal guidelines allowed tiny merge lanes and before highway traffic patterns shifted as people moved to the suburbs.

To the angry motorist refrain of "What were they thinking?" Mr. Kravits of PennDOT says, "What they were thinking was the best solution for the time. The traffic patterns changed. I am sure people will sit back in 50 years and say, 'What were those traffic engineers thinking?' "

PennDOT has been making small improvements to some Parkway exits, having lengthened the de-acceleration lane at the Bates Street exit of the Parkway East and adding yield signs and lane markers on the Boulevard of the Allies on-ramp to Parkway East outbound. Next year, it planned to reconfigure a much-maligned merge -- the Carnegie exit onto the Parkway West toward the airport. The agency hopes to rework the intersection by turning the shoulder into a third lane so mergers will have their own lane.

But with all the bridges and hills around, he says, there is only so much engineers can do. The only way to fix the merge outside of the Squirrel Hill Tunnel, he says, would be to close one ramp, which would cause too much traffic to be rerouted onto other roads.

Fortunately, he says, Pittsburgh drivers usually pull over and let mergers in. "We have very accommodating drivers. Otherwise, it would be a different ballgame."

But our readers saw some examples of bad merge etiquette out there.

"Pittsburghers seem to think the upside-down triangle at the end of the merge ramps means "STOP." Merging into traffic from near zero is always dangerous, and the cause of most traffic backups," says Geoff Marton, 34, a trainer who lives on the South Side.

The best way to merge is to keep pace with traffic -- even go a few miles faster, says Alex Hunter, a Colorado consultant who runs Rush Hour Relief. He has helped drivers who are so paralyzed with merge fear that they had stayed off highways.

"If you get on the ramp and accelerate, there is almost always a place to fit in," says Mr. Hunter.

But Mr. Kravits says you don't want to be too aggressive, the cause of many accidents. An aggressive merger tailgating a timid one can cause a crash.

Some drivers say part of the drama of merging is getting caught between different driving styles. Mr. Simon of Squirrel Hill does play-by-play of the merge from Beechwood Boulevard onto the Parkway East outbound, sandwiched between two cars.

"Wait -- the guy you thought was in front of you, which you thought was long gone, is sitting 20 feet ahead, guilty of a false start. And watch for the driver behind you, trying to piggy-back into traffic along with you. It's Murphy's Law of the road. The guy ahead is too tentative, the one behind you, too aggressive. When all of this comes together at Death Row, it's an exhilarating thrill-ride."