When I moved from NYC to Spain, I asked 2 strangers twice my age to be my biking buddies. We formed an unexpected, lasting friendship.

• I lived in Spain for a year and wanted to mountain bike there, but I didn't want to do it alone.
• One day, I asked two strangers I saw fixing a tire if I could join them someday, and they agreed.
• We quickly became friends as we adventured and still keep in touch today.

In 2017, at age 31, I moved from New York City to rural Spain to teach English for a year. On the way to school on the first day, I spotted a thin, tantalizing trail winding through the dehesa, a landscape of rolling hills, burnished grass, and lonely cork and oak trees. I loved mountain biking, but the previous summer, I had been chased by dogs on a solo ride, and I'd fallen badly. I was too afraid to explore that landscape alone.

I bought a used bike and started commuting to school, an hour each way. I never saw a dog, but the sound of barking — often imagined — regularly sent me into a panic.

One morning, I saw two men in their late 50s or early 60s stopped at the side of the road, examining their bikes.

"Need help?" I said.

"Thanks, we're just putting the chain back on," said one.

I had a crazy idea. "You guys bike the trails around here?"

The answer was yes. They were locals and biked the dehesa every weekend.

I gulped. "Do you think I can come with you sometime?"

A foreigner half their age, I got skeptical looks, but we exchanged numbers. I soon had second thoughts. We didn't have anything in common, and the three of us would be bored, awkward, and miserable. I should find people my age. But they called, and my yearning for the trail won.

They gave me a test, and I passed

Pedro and Angel took me on a four-hour ride from the riverside to a valley piled with boulders, to an oak-shaded lane, and finally, to what looked like a fort of massive stone slabs sunk into the earth. It was a 4000-year-old tomb, or dolmen. As we stood around drinking water and feeling pleased with ourselves, it wasn't awkward at all.

Without saying much about it, we became inseparable, three overgrown kids running riot through a fairy-tale landscape. We spun around a Roman reservoir, climbed to a 9th-century Arab castle, blazed through fields of wildflowers in spring. I wondered why the rides were usually shorter than the first one, and my friends admitted, laughing, that it had been a trial by fire. But I'd passed.

From that point on, we were a trio

Tall and broad, Pedro was a solid and disciplined rider with a steady demeanor to match. Angel, on the other hand, was a firecracker, small and noisy, constantly cursing and joking. Pedro kept Angel going, and Angel sparked Pedro's mischievous side. ("How are those churros treating you now, Angelito," Pedro taunted as Angel, cursing, struggled up a steep hill.)

My integration wasn't totally smooth. On an early ride, I thought Angel was babying me. I asked him to treat me like another buddy, not his daughter. To my shock, he listened. I had come to believe that men, especially ones my dad's age, couldn't listen, much less change.

One day, we were biking past a farm, and three barking dogs came shooting up to the fence. I almost jumped off my bike. When I explained why, Angel and Pedro rode on either side of me past the dogs. (True to his promise, Angel made fun of me as if I were one of the guys.) On later rides, they escorted me past grazing cattle and even two massive wild boars. In time, my body didn't crumble at the sight of an animal. Something besides my calves and lungs was getting stronger.

During a thunderstorm one day, while we sheltered in a railroad tunnel, Pedro stayed on his bike, grabbing the wall for balance. His knees were shot, he said, and would be replaced that summer. I couldn't believe it; I spent every ride eating his dust.

Summer came. Just before Pedro's surgery, I suggested we bag a prize Pedro had been eyeing: the tallest hill in the region. After a grueling climb up a seemingly endless switchback, we were hugging each other and enjoying the view. On the way down, I hollered like a wolf, freer than I'd been in years.

I left Spain, but we still keep in touch

In August, just before I left, Angel and I hit the trails at midnight to avoid the heat. With the full moon bathing the dehesa, we barely needed our headlamps on our way to the dolmen. Angel told me that he and Pedro couldn't believe the coincidence that had connected them with me: the foreign lady whom they now considered a true friend.

"It's these things that make life worthwhile," he said. "And you can't buy them or plan them."

I agreed. Their friendship — like the swaying trees, the stars, the ancient stone — was a gift, not something I could have taken by force of will. I felt humbled.

After I left town, I did something I had always wished I was brave enough to do: a two-week solo walk through the countryside. I have no doubt that the courage came from my friends.

Since leaving Spain, I've kept in touch with Pedro and Angel. I usually manage to have dinner with them and their wives once a year. We still laugh at our unexpected friendship. Pedro has two new knees now, so I've been joking about doing the Camino de Santiago, a bucket-list adventure for all three of us. Who knows, maybe we will.