Implausible: Slagforce
From industrial wasteland to recreation destination
On Easter Sunday, Sylvie got spooked by a train while she was off-leash and ran away from Renee. Like the box turtles, deer, and (unfortunately for me) snakes that have been displaced by the remediation in The Slags, the dog pack has had to seek out a new habitat. They were meandering along a trail directly below The Slags that follows the Monongahela River. When I say directly below, I mean that literally. The most direct route would have been a 100-foot fall off the southern edge of The Slags, but they opted for the easy way down — in a car on a road to a trailhead. (Cowards!)
The trail also happened to follow railroad tracks. Next to plastic buckets and her own shadow, Sylvie’s greatest fear is large vehicles and the noises they make. As Renee described it, the moment the train whistle blew, Sylvie bolted. She tore off the trail and disappeared into the brush on the hillside, the sounds of dog whistles and shouts of “SYLVIE!” drowned out by the passing train. By the time the 80-car train had finally passed, Sylvie was long gone.
We were about an hour from home when we received the panicky phone call from Renee. After a few seconds of watching my happiest memories of Sylvie flash before my eyes, I put the word out to neighbors that she was missing. I made myself believe that if Sylvie could find her way up the side of the cliff and a mile downriver back to The Slags – a route she’d never taken before – that she could make it home.
Friends and neighbors jumped into action. Our neighbor across the street stuffed her pockets with chicken and headed into The Slags, ready to intercept Sylvie should she end up there. Some friends a few streets over put their baby in her stroller and started walking toward our best guess as to where Sylvie might pop out of the brush and into the neighborhood if she didn’t go back to The Slags. Yet another family put their dog, Gem — Sylvie’s best friend — out in the yard while they finished preparing their Easter ham in the hopes that Gem would act as some kind of adorable, pointy-eared homing beacon that would lure Sylvie to safety.
Twenty-seven minutes later, our next door neighbor, Marsha, called with the good news: Sylvie was home. Marsha had planned to keep vigil on our porch all day if need be, but Sylvie sauntered up the driveway grinning from ear to ear in less than half an hour.
The next few days were spent marveling at how she did it. “That’s one smart pup!” neighbors would call from their yards when we walked by. “Does that dog have GPS?!”
Stuck in traffic, my mind would drift to scenes of Sylvie bushwhacking her way through invasive honeysuckle and scrambling up and over shale outcroppings, her hind legs dangling precariously over the edge like a character in Homeward Bound.
Then I had a beer with Rob Pell, the co-founder of Slagforce, a renegade trail building group, and had to laugh when I realized that Sylvie simply followed his mountain biking trails back to The Slags and then home like she was out for her regular Sunday stroll, albeit with a massive surge of adrenaline and cortisol.
Rob, his co-founder Darrin Filer, and their mountain biking buddies who eventually became Slagforce, have built over 15 kilometers-worth of trails in and around The Slags. The trail Sylvie most likely took to find her way home is called Humpular, a long, “flowy” singletrack with an elevation change of 143 feet and at least a dozen blind corners. In addition to breathtaking views and a plethora of advanced mountain biking features, Humpular is also Slagforce’s origin story.
Darrin and Rob built the first section of Humpular, then known as “Crater Trail,” after years of secretly building and connecting trails in Frick Park. Both men were volunteers with Trail Pittsburgh, a non-profit that constructs and enhances trails within the existing park systems in Southwestern Pennsylvania, but their vision was bigger than what the powers that be would allow.
“We were working in Frick (an official Pittsburgh city park) but we had all these ideas,” Rob tells me at Pub in the Park, a neighborhood spot that was filled with mountain bikers the night we met. “We had designs for the whole park. Mountain bikers separate from hikers – everyone could be happy.”
Like with everything, though, politics got in the way.
“Even though it was the mountain bikers who built all the trails, we were just one of many user groups. Any time we built a new trail, the Audubon people freaked out.”
Rob and Darrin pitched their ideas for years but, according to Rob, the head of the Department of Parks and Recreation didn’t want any headaches, so he kept saying no. Never ones to be deterred, Rob and Darrin snuck their shovels into Frick on off-days and started constructing trails in secret. While they enjoyed seeing their designs finally come to fruition, after a while they realized their guerilla trails were creating trouble for the trail steward who had to answer to his boss at the Parks Department.
“We never told him that we were the ones who did it,” Rob tells me sheepishly. “I’m sure he knew it was us, but we wanted him to have plausible deniability.”
So, in 2011, Darrin and Rob took their talents about a half-mile southwest, to the slag heap bordering Nine Mile Run, a creek that feeds the Monongahela River.
Rob first rode The Slags in the 1990s.
“‘92 maybe,” he says, grimacing a bit before asking how old I was in 1992.
“You don’t want to know,” I tell him. (I was 4.)
As far as Rob knows, the original trails in The Slags were built by kids in Swisshelm Park and a now defunct group of off-road cyclists. The opportunity for adventure at that time was limited to just a few short trails, but Darrin and Rob saw potential in the large drops created by the various piles of slag.
It was Darrin who built the first Slagforce trail. He named it “Crater Trail,” as the trailhead was a “skinny” bridge spanning a sinkhole. (Classic Pittsburgh.)
“At first I was like, ‘Cool!’ says Rob. “But then I went home and Googled sinkholes and got totally freaked out that it would collapse and we were going to get sucked in.”
While the fear of being buried alive would deter most people, Rob is not most people. He flew down the trail and was instantly hooked, until he realized the only way back up was a long, slow push to the top. “I told the guys, ‘I’m never riding this trail again if I have to push my bike up to the top over and over.’”
Rob isn’t lazy; quite the opposite. He just wanted more action.
“I thought the trail should go all the way to the bottom of Nine Mile Run,” where it would then exit onto the existing city bike and walking path. “They didn’t think it could be done.”
So, Rob did what Rob had always done – he built the trail himself from the bottom and connected it in 2012. The trail is now called Humpular — so named because it is very “humpy” — and with the additions that Slagforce has made in the last decade, it now includes a 5-kilometer loop going the opposite direction.
“If I’m being totally honest,” Rob tells me, “When I started on Humpular, my goal was just to be able to ride my bike from my house in Point Breeze to Brew Gentlemen.”
Brew Gentlemen is a brewery 4.5 miles from Point Breeze by car in the neighboring borough of Braddock and, depending on which roads are closed any given day, can require traversing either a tunnel or a bridge or both. I can’t blame Rob for wanting a less soul-crushing route to drink his favorite beer, but it never would have occurred to me that the best route would run along an overgrown cliffside with only a two-foot wide trail separating the rider from a painful splash in the river below.
Even Rob admits that his first time walking this route before the trail was built was terrifying.
“It wasn’t so much walking as it was crawling – under downed trees, around thorny brambles, across the rocks sticking out of the cliff.”
After that first death-defying hike, Rob had his doubts that building a trail would even be possible. But the call of extra hoppy IPAs and the adventure-seeking spirits of the other Slagforce members eventually lured him back to the woods along the cliff. “We just kept making more and more jughandles over 10 years, and eventually Humpular went all the way to Les Getz Park.”
But Les Getz Park was only halfway. In February 2021, when most Pittsburghers were succumbing to their Seasonal Affective Disorder, Slagforce was mapping and flagging a second major trail on the Brew Gentlemen Throughway called Redemption Center. Redemption Center was named after the official Slagforce stash location (more on that in an upcoming piece!) and just over two years later the 1.1km loop was finished, complete with tabletops, ladder drops, and something called a megabooter. (That last feature is made up, right?!)
Call it vision or hedonistic pursuit, in the process of making the Brew Gentlemen dream come true, Darrin and Rob unintentionally built a movement. Slagforce – officially named in 2021 – is a no ragtag band of dirtbags with shovels hacking away willy-nilly. Each trail they design is carefully engineered to consider grade, drainage, sightlines, and safety while incorporating natural features and ensuring sustainable design that won’t succumb to erosion. They have a Signal chat, weekly status reports, a website, and a bank account.
In 2024, Slagforce spent $7,000 on trail building – all of it sourced directly from builders, riders, hikers, and others who appreciate their work, myself included. (If you’d like to buy the builders a shovel or a beer, click here.)
And the day jobs of the members themselves read like a roster of the modern day Village People. “We’ve got software developers, a lawyer, a dentist, a restaurateur, a librarian, engineers. One of the guys worked at SpaceX and now he does drone racing.”
“Everyone is f*cking brilliant, and then there is me.”
While Co-Leader of Guerilla Trail Building Army may not fit neatly on a resume, there’s something to be said for creating something out of nothing, especially when that something is so alluring it brings in mountain biking pilgrims from as far away as Australia. Even more so when you find out it’s all because some guy just wanted to have a beer without getting in his car.
Today, only 3.2 kilometers of brush separate Rob from his original goal of riding his bike all the way to Brew Gentlemen. Building on the final trail, Blastphemy (a play on Carrie Blast Furnaces situated just below), is currently underway. Never ones to take the easiest path to any destination, Slagforce’s Blastphemy will take advantage of the terrifying natural terrain along the Monongahela River to include drops up to 15 feet tall, some of the tallest in all of Western Pennsylvania. Don’t forget to wear your helmet.
As for how Slagforce is dealing with the remediation of The Slags? It will come as no surprise that they’re a few steps ahead of the authorities. When the remediation and solar farm projects were announced in 2024, Sylvie and I couldn’t walk through The Slags without seeing the telltale signs of Slagforce – shovels, buckets, and overturned wheelbarrows tucked neatly under bushes just off the trail. A flurry of new trails popped up seemingly overnight, all of which I’ve since learned were built as additional access points to be used when remediation activity cuts off the original trails.
But being ahead of the game doesn’t immunize anyone from the sadness of seeing a place they love destroyed. “As a rider myself, I wish they’d save the trees and bulldoze the trail,” a Slagforce rider commented in response to a post in the neighborhood Facebook group outraged over the razing of a stand of mature trees that weren’t in the original tree removal plan. “The trail can be rebuilt, but there won’t be a forest here again in my lifetime. Those trees were older than me.”
