We first met in 1998. The old bicycle was a gift from a friend. I welcomed my new roommate excitedly, despite having zero storage. (My rented room was so small, I had to lie diagonally in bed in order to stretch out my arms.) I bought a strong hook, hung my new two-wheeled pal on the wall, and proceeded to ride everywhere together. We hit the gym, met friends for drinks, and enjoyed dazzling summer sunsets [1] over [2] the Hudson River [3]. On these cheap dates, with no subway or cab fare, I got into the best shape of my life.

We moved from that seven-foot-wide room in an elevator building into a studio apartment, a fifth-floor walkup where I had to carry us both up and down a narrow, steep stairwell. Here, we shared a home, but saw fewer sunsets together. I began walking more often. I pretended things hadn't changed, but we were drifting apart. Still, when the West Coast beckoned, we took the 3,000-mile plunge together.

In San Francisco, we could finally spread out a bit in a multi-room apartment (and have a more satisfying stretch in the morning). My onetime constant companion moved into the garage; the wall mount became an obsolete, inconvenient reminder of those early blissful years. We dreamed of a few simple bike rides, but the obstacles seemed too large and too numerous, the foremost being the city's famous hills [4].

Once, we cycled across the Golden Gate Bridge, hoping to recapture the past, but the tourist throngs with their rented wheels [5] provided a metaphor all too obvious: we were all just going through the motions. Months later, we tried riding around the waterfront, only to get a flat tire far from home. I left my mate chained to a post, grabbed a cab, and returned with my car, defeated.

I appealed to friends for help. One suggested a jaunt to Berkeley's Wildcat Canyon, a strenuous 8k dirt trail with the dual hazards of cow chips and cattle guards [6]. Another friend suggested an "easy" ride to a town 20 miles away. Still smarting from my flat-tire drive of shame, I politely declined both overtaxing offers. I needed to start small. Then one day, I stumbled upon a path that—however elusive and winding—promised to give our frayed relationship a boost.

When I first heard of a local legend called The Wiggle [7], I thought it might be a ritual dance from Burning Man [8], or perhaps slang for some mind-warping altered state [9]. For all I knew, its bohemian devotees might proudly call themselves "Wiggleheads." But no, The Wiggle, which forms the heart of San Francisco Bicycle Route #30 [10], guides its followers through several of the city's most famous peaks as if on a carpet ride, magically avoiding any steep inclines with an artfully choreographed sequence of zigzags left and right. For decades, the secret of The Wiggle was passed down by word of mouth, like a carefully guarded recipe, but last year, it was exposed via newly posted signs, part of a citywide effort to paint more bike lanes [11].

I pedaled across town under an overcast sky and arrived at a sign reading, "Welcome to the Wiggle"—high above broken glass, pigeon poo, and an alley of homeless people and their shopping carts [12]. Undaunted, I rounded the block and began the prescribed wiggling one block further. Right onto Steiner, left onto Waller, right again onto Pierce... it was like therapy. I felt my lungs expand, my heart thump, and my neglected relationship starting to heal. The bike lane merged briefly onto a busy road, then popped out into The Panhandle, a long thin strip of cool green adjoining Golden Gate Park, with its myriad possibilities [13] for walkers, cyclists, and those who fall somewhere in between, like myself.

The 30 minutes flew by, and the return trip went even faster. Riding The Wiggle felt as easy as riding a down elevator and cruising towards the Hudson River once did. Was it a coincidence that in both cases, we were heading west, towards a setting sun?