His packing advice couldn't have been simpler: "Throw a loaf of bread and a pound of tea in an old sack and jump over the back fence."
That's what I've done — more or less — and now, as evening descends, I'm a two days' walk from the trailhead with little more than a toothbrush and a change of socks in my daypack.
Muir used to shiver through the long, frosty Sierra nights in hollow logs, but I'm looking forward to a bit more comfort: a reasonably comfortable bed in a heated tent cabin, a hot shower, flush toilets and a four-course dinner that the Ahwahnee Hotel would be proud to serve.
My destination is the Merced Lake High Sierra Camp, one of five semipermanent camps in the back country of Yosemite National Park. Accessible only by foot or horseback, they open up some of the park's premier high-country trails to those who would rather not walk hunched over with half the contents of the REI catalog on their backs.
The camps have existed in one form or another since 1916 — they were the brainchild of Stephen Mather, the father of the National Park Service — yet they remain off the radar to many Yosemite visitors. Those in the know apply for openings through a lottery system each fall — last year 3,300 people competed for 850 slots — or work the busy cancellations market that typically opens up around Memorial Day.
Perched next to frothing rivers, granite-lined lakes or alpine meadows, the camps sit at elevations between 7,000 and 10,000 feet and are a moderate day's walk — eight to 10 miles — apart.
It's about as close to European-style, hut-to-hut hiking as we get in the U.S., although the camps — particularly Merced Lake, with its campfire circle, horseshoe pit and big stack of board games — feel more like summer camps for hikers.
The season typically runs from late June or early July through mid-September, but mountain weather inevitably calls the shots. This year Glen Aulin is scheduled to open July 15; May Lake, July 22; Merced Lake and Vogelsang, July 28; and Sunrise, Aug. 3.
Many spend six days or more walking the full high-camp circuit, but with limited time last September, I chose to hike an abbreviated loop by way of the Sunrise, Merced Lake and Vogelsang camps, circumnavigating the stony battlements of the Cathedral Range above Tuolumne Meadows. (The two other camps — Glen Aulin and May Lake — lie north and west, respectively, of Tuolumne Meadows.)
At the trailhead I hopped off the free shuttle bus with three traditional backpackers, and as we shouldered our loads I couldn't help but feel guilty. They staggered backward under burdens that must have topped 45 pounds; I could lift mine with my pinky.
I've been walking these trails since I was a teenager, but being unshackled from a heavy pack was a revelation: I felt like Buzz Aldrin bounding across the lunar surface in micro-gravity.
Instead of pushing for miles I could linger to admire an alpine tableau, skip stones in a timberline tarn, watch cloud shadows scud across distant peaks, exchange world views with a chubby marmot or nap on the shady bank of a burbling stream — all the things you come to the wilderness for, yet too often are too harried or haggard to do.
Once I even spent the better part of an hour watching Muir's favorite bird — the water ouzel, or "dipper" — dive again and again into a cascade. It appeared to fly underwater, then hopped out to perform a goofy little dance on the rocks.
By early afternoon I'd followed the John Muir Trail over 9,680-foot Cathedral Pass and arrived at Sunrise High Sierra Camp, which overlooks a long, deer-filled meadow that brought to mind an alpine Serengeti.
In the cavernous dining tent, camp manager Konrad Maurer offered me a glass of chilled lemonade as he checked me in. Families are housed together in one of the tent's nine tent cabins – 7 is the minimum age — and individual hikers like me usually bunk with strangers of the same sex.
Built on raised concrete slabs, the tent cabins are furnished with four squeaky, metal-framed beds with lots of scratchy wool blankets — it's a good idea to bring your own cotton or silk sleep-sack — a small but overachieving wood-burning stove and a card table. The canvas walls and roof are taken down at the end of each season.
The nightly rate is about $150 a person (it varies slightly from camp to camp), which includes breakfast and dinner but not lunch. Sack lunches are available for $15.25.
As I dropped my daypack on an unclaimed bed, Maurer instructed me to pull out anything vaguely food-like — including sunscreen — and stow it in one of the heavy metal lockers scattered around the camp. Years ago the High Sierra camps were notorious bear magnets — you could expect two or three ursine visits a night — but greatly fortified storage for food and garbage has pretty much solved the problem. "We had one bear skulking around earlier this summer," Maurer told me, "and I don't want any repeats."