It's midday at Citizens Bank Park. A wayward tour group of children bantering and cartwheeling outside the souvenir shop is rounded up by chaperones and herded back onto a bus. A family of tourists pausing to gaze up at the structure that its favorite team calls home is hurried along by an impatient teenage sibling.

There is nowhere near the cacophony of fans, sports, and peanut vendors that fills the air here at game time as Matt Stoltz arrives on his bicycle with sleepy eyes, intense tan lines, and a patch of poison ivy battling for dominance on his lower right leg.

He's pretty sociable for a man who has traveled so far and is partially covered in dermatitis. "I hit my 9,000th mile today, I think," he says with a weary grin.

Stoltz has been showing up in every city with a Major League Baseball team all summer – 21 cities so far, since setting out from Seattle on opening day (April 6), with the other nine still ahead of him. He has just arrived from Washington, where the Nationals shined a spotlight on his cause: Biking for Baseball, a Denver-based nonprofit, which "promotes and empowers youth and youth mentoring programs through cycling, baseball, and coaching."

A child of Wisconsin dairy country - it's the Milwaukee Boys and Girls Club that will receive the more than $20,000 in donations Stoltz has gotten for his ride thus far – Stoltz just graduated as a Wisconsin Badger in December and embarked on this trip under the logic of "I'll have the rest of my life to work."

Biking for Baseball and its mission have existed since 2012, and as a lifelong fan of both aspects, Stoltz volunteered for and organized this summer's six-month sojourn with the organization's help. He is covering all the costs himself so that 100 percent of the donations can go to use, and hopes that B4B will continue to arrange causes such as this.

But what would motivate a 22-year-old to take on such an altruisitic endeavor, giving him more completed charity work than most people have done into their 40s and 50s?

"It's just something I've always wanted to do," he says. "My parents did a good job raising me with a background of getting involved and making a difference. They instilled in me at a young age that if you want to make a difference, you've got to work at it and take action. There's a way to make anything happen, so that led me to my various charitable endeavors over the years."

Stoltz has been a part of a number of causes, from the Boys and Girls Club in his hometown to six months of work with youth in Kenya. "This one is another big one," he says, "and we'll see what's in store for the future."

However, the administrative leg of the experience ended long ago. Then came the 11,000 miles of pedaling, and even now, with 9,000 of them behind him, it's tough for Stoltz to fathom.

"It's really crazy to look back at a map. … It still hasn't really hit me," he concedes. "Sometimes I wonder, 'How the heck am I here?' I suppose once I finish the trip and the dust settles a bit, then I'll really realize what I just accomplished."

Most tourists will simply hop a plane and fly over the more savage corners of the country, or drive past them on highways built to turn traveling into an 80-m.p.h. experience. But on a bicycle, Stoltz explains, "You notice everything.

"You're on back roads and you really travel with the land. The wind, the smells, the terrain, you get that sense of where you're riding. It's a very cool way to see the country."

Chronicled in pictures and tweets, Stoltz's story, to the casual viewer, appears to be an amicable yarn of smiles and hugs from mascots. But the part people don't see is the journey itself; the cycling, the sweating, the chafing, the literal uphill battles, and the miles upon miles of American animal carcasses sizzling in the August sun.

"You notice if the type of pavement changes. You notice if the wind shifts. You notice different crops," Stoltz says. "But yeah, there's a lot of roadkill, and it always happens to be sitting right in the middle of the bike lane. So you usually get a good whiff of that."

Stoltz just shrugs and blinks at the question when asked what he'd do in an emergency out on the road by himself. "Call the local authorities, I guess?"

Already putting in 110-120 miles a day, he can't put in extra time to find hotels and campgrounds, relying on the roofs of local strangers to keep him out of the harsher elements. When that's not available, well, he's got his camping gear compactly stored on the back of his ride.

"I've had to do that more than I'd like," he says of stealth camping. "But I've gotten good at it. You just find some woods, set up right at dusk, and nobody's going to come and bother you."

Of course, sometimes he's the only one trying to camp somewhere for a reason.

"Having to stealth camp in Florida wasn't fun because it was so, so hot," he recalls. "You just sit in your tent and sweat until about 11, then it cools off a little bit and maybe you get a few hours of sleep before packing it up and doing it all over again in the morning."

Sleeping is more of a luxury than a necessity on this type of trip, but Stoltz does have one distinct advantage: "It's a lot harder to fall asleep while you're biking than while you're driving."

You won't find Stoltz snoozing on a pile of toxic industrial sludge off I-76 East, however, as thankfully he has managed to find lodging in South Philadelphia during his stay here. Wednesday served as a rare off day for him to recover before watching Game 3 of the Phillies-Dodgers series at Citizens Bank Park on Thursday and then setting out for Yankee Stadium.

When it's tough to roll out in the mornings, Stoltz says he only has to remind himself that there are kids out there whose daily challenges are far greater than "having to ride a bike everyday."

"You just kick yourself and remind yourself what the trip's really about," he says. "That kind of pushes you and inspires you. Those are the kids you want to help. On tough days, that's always in the back of my mind."

Having already barreled down California and pushed through the dry heat of the Southwest and over to Florida's unforgiving swamps, Stoltz is headed north to New York, Boston, and Toronto before banging a sharp right toward the Midwest. Stoltz's hometown Brewers' Miller Park will be the penultimate stop on his passage, at which point he will begin his next adventure:

"I'm probably going to sleep for four days straight."