Back in April, a crowd of eager bicyclists tapped their toes as patiently as they could while waiting for a line of rain-spewing, charcoal-colored clouds to pass over a small Texas town.

A hundred or so of them packed into a metal barn, where organizers of the Castell Gravel Grind had set up race headquarters. Others huddled inside vehicles or moved into a community church across the lane as lightning flashed, thunder cracked and raindrops fell.

When the skies finally cleared two hours later, they lined up in front of the bright yellow Castell General Store, awaiting the start of a delayed and shortened bike race that would take them over plenty of rain puddles on dirt, gravel and sand roads that twisted through the Hill Country west of Llano.

Gravel grinding, it turns out, is a thing.

It differs from road riding, in which cyclists pedal sleek, aerodynamic bikes with skinny tires over paved roads. It differs from mountain biking, too, with its beefy, knobby-tired bikes designed to scamper over tree roots and up rocky ledges. It even differs from cyclocross riding, with its loops on a dirt track peppered with jumps and drops.

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Gravel riding takes cyclists off heavily used city streets and puts them on rural gravel roads where they can pedal with less worry that cars will whiz past traveling 80 miles an hour. Sure, they might have to slog through patches of soul-sucking sand or bump along washboard stretches of country alleys, but that’s half the fun.

“The first thing is there’s no vehicle traffic,” says Alan Gielen, 58, of San Antonio. “It’s safer. And the nature — I’m relaxed and feel free and at peace compared to riding in the city, where I’m all tensed up.”

Gravel riders tend to be less intense about their racing, too — “the pros mix with the Joes,” as gravel rider John Wilmeth, 37, of New Waverly puts it — and the post-ride beer ranks high on the list of crucial amenities.

Here in Central Texas, bike shops are suddenly stocking gravel bikes, which look like a cross between a mountain bike and a road bike, with beefier tires but a more aggressive rider position. (If you don’t want to invest in a gravel-specific bike just yet, you can get by on a mountain bike, a cyclocross bike or even a hybrid, but the skinny tires and delicate constitution of a road bike just won’t do.)

“I think it’s more exploratory and less cutthroat or competitive,” Venny Alub, 31, says of gravel riding. “I race, too, so I love all sides, but when I’m tired of racing or get burned out I go to gravel.”

Austin residents Mike Drost, Debbie Richardson and Janie Glos came up with the idea for the Castell Gravel Grind six years ago, after biking some of the dirt roads around Castell, a small town with not much more than a general store that serves barbecue, a post office and a few rental cottages next to the Llano River.

“We came out to ride on a whim and stayed for the weekend,” Glos says. “We thought, ‘Wow, this is such a cool place. What if we could get a bunch of friends and put on a race?’”

Six years later, the 2019 event sold out an hour after registration opened, fueled not by paid advertising but via past participants sharing photos on social media. Organizers capped participation at 500 and offered three distances — a full grind of 100 kilometers (which filled in 21 minutes), a three-quarters grind of 75 kilometers and a half-grind of 50 kilometers.

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People love the event because it keeps them off the high-traffic roads of most organized group rides — and they like the casual vibe.

“Gravel racers are a more laid-back group,” Gloss says. “They’re a fun group, and they enjoy their beer afterward.”

The race route this year took cyclists over cattle crossings and past fields of wildflowers — and up a notorious stretch of sand on Keyserville Road where, as some riders described it, “the carnage happens.” Dry sand can slog down a bike tire, and lots of cyclists end up walking their bikes (or tipping off them).

“Those sand pits can really catch you off guard,” says Gielen, the San Antonio cyclist. His bike is equipped with plus-size tires to help it float through dry, heavy sand. “It is a grind. This is not a walk in the park.”

Still, those challenges create part of the appeal for some.

Wilmeth started racing road bikes and mountain bikes 11 years ago. These days he likes gravel riding for its inclusive community and varied terrain.

“You get all the different obstacles that make it interesting — you may get mud, you may get river crossings. It makes it an adventure,” Wilmeth says.

And here in Castell, the small-town vibe and burgers served up at the general store are worth the trip, too, says Alub, who ended up winning the overall women’s title at the race.

That’s another thing about gravel riding for her.

“You can go out and it’s just another group ride, or you can go out and try to stay with the front group and see where the day takes you,” Alub says.

This day took her to good places, despite the storms that delayed the start of the race.

Alub stood on a makeshift podium in front of a stack of firewood and showed off her award — a wooden block about the size of a pint of blueberries.

Not bad for a day on the gravel.

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