A few days after Tim Kaine saw his vice presidential hopes dashed, a visitor showed up in his Senate office.

“Tim, I’m the only person in the Senate today who knows exactly how you feel,” John McCain told him, pointing to his own failed campaign for president in 2008. The Arizona Republican’s suggestion? Get back to work immediately.

“I’ve worked hard to follow John’s advice,” writes Kaine, describing how he shoved his feelings away like dirty gear in a rain-soaked backpack. “This part of hiking has always struck me as a good metaphor for life. … When conditions are bad, you stuff everything in the pack and start walking.”

And later, you write a book — part wilderness journal, part political memoir — to sort everything out. In “Walk, Ride, Paddle,” Kaine is still smarting from Hillary Clinton’s loss to Donald Trump, but trekking 1,228 miles across his home state of Virginia gives him time to reflect. He stares down a bear, marvels at nature and accidentally pours boiling water on his foot. 

He dubs the trek the “Virginia Nature Triathlon,” which includes hiking the Virginia portion of the Appalachian Trail, cycling the Blue Ridge Parkway and Skyline Drive, and canoeing the James River. For him, it takes three years, divided into chunks from 2019 to 2021 that align with legislative breaks.

About 3 million people use the AT each year, but few of them are sitting senators. And Kaine’s staff and colleagues weren’t sure what to make of his plan.

“Some of them thought I was nuts. I remember Angus King (I-Maine) was like, ‘You’re gonna what?’” Kaine said in an interview. The trip was an attempt to explore Virginia’s natural beauty, tourism industry and history, including painful parts tied to the Civil War and slavery. But it was also an excuse for Kaine to collect his favorite quotes from Henry David Thoreau and take stock of his career.

“I do think that I was probably subconsciously wanting to recharge my battery and gain new energy and new perspective for my next chapter in public life,” Kaine said.

Kaine isn’t the first politician to document his travels. Democratic Sen. Christopher S. Murphy does an annual walk across Connecticut, and in earlier decades, Republican Lamar Alexander walked across Tennessee wearing a flannel shirt as he ran for governor in 1978. In a more sordid saga, “hiking the Appalachian Trail” became a euphemism in 2009 as South Carolina Republican Gov. Mark Sanford tried to cover up his whereabouts during a trip to see his lover in Argentina.

But Kaine — who earned the trail name “Dogbowl,” because he carried a collapsible dog bowl to wash up — is particularly frank for a politician about the physical realities of life on the trail. His may be the only memoir where a senator talks about waking in the middle of the night to pee in the woods, or about his morning bathroom routine.

“If I am near a shelter, an hour of motion gives my digestive system time and inclination to use the privy — so much easier than breaking out the trowel along the trail,” Kaine writes. 

Kaine said he kept a journal in real time and added notes after the fact. Parts are standard political fare, as he rattles off a list of his accomplishments or warns against the continued threat of Trump, calling him “a symptom of a national sickness.” Other parts are confessional, as he describes the feeling that he let down Clinton and other women. The rest reads like a travelogue, filled with daily accounts of peaks he climbed or meals he ate.

His trek can feel like a relic of an earlier time. Despite a climate of heightened political violence, Kaine sometimes travels alone, even through parts of the state where a Democrat might not be warmly received by the average voter. Sounding more like a Beat poet than a U.S. senator, he casually references hitchhiking to a trailhead, as many AT hikers do. 

“They blend in pretty well back in the woods, don’t they?” Kaine recalls joking with members of one curious group who ask whether he’s traveling with a security detail.

When he does mention the dangers of the trail, they’re usually of the natural variety, like “widow maker” tree branches that could fall from above. He comes face to face with black bears, takes his canoe through treacherous rapids, and contends with the threat of dehydration while hiking in Virginia’s August heat. But ticks are perhaps the biggest threat. Kaine mentions his former Senate colleague Kay Hagan, a North Carolina Democrat who died in 2019 after developing complications from a tick-borne virus. Even still, he’s got a sense of humor.

“I wear my shorts with casual insouciance, indeed abandon. But hey — I always walk on the wild side,” Kaine writes, explaining his choice to forego long pants, which can shield against tick bites.

He also confronts his age. Kaine, now 66, conceived of the idea for the trek around his 60th birthday and his 25th year of public service. By that point, Kaine had been a councilmember and mayor of Richmond, Virginia’s lieutenant governor and then governor, and, since 2013, the state’s junior senator. He’s currently running for a third term in a race that Inside Elections rates “Solid Democratic.”

Kaine is hardly old by Senate standards, but he makes much of his being a sexagenarian.  Throughout the book he battles the aches and pains that accompany sleeping on a mat outside, often recalling earlier days when his joints were less creaky and sore. 

“How much longer before day hikes will be the extent of what I can attempt?” Kaine wonders early in the book.

Despite the existential dread, Kaine has earned a reputation among his colleagues as a trip planner when senators are stuck in town for a long weekend. He’s organized excursions to D.C. monuments like the Frederick Douglass National Historic Site, President Lincoln’s Cottage and Rock Creek Cemetery.

And he’s recently embarked on more physically demanding outings, like biking from Pittsburgh to D.C. in 2022 with his oldest son. The next year, he and some friends hiked the High Route in the Alps, a multiday trek from Mont Blanc in France to the Matterhorn in Switzerland. 

“I don’t think I’m going to do anything other than a weekend hike this year because it’s an election year and I’ve got to eat my spinach,” Kaine said. “But I suspect I’m going to try to have some fun outdoor adventure to look forward to every year for a very long time.”

“Walk, Ride, Paddle” (Harper Horizon) is out Tuesday. Kaine will appear Thursday at Politics and Prose on Connecticut Avenue in Northwest.