In late August, I convinced some friends to go on a day trip to a small northern Iowa town about 200 miles from the Twin Cities to see the Grotto of the Redemption.

I was excited to see this 100-year-old spiritual, artistic and geological wonder in West Bend, Iowa, designed and constructed — mostly by a German priest — with thousands of rocks and precious stones. My friends were interested, too, but as I learned later in the day, they had a slightly different perspective.

A grotto is “an artificial recess or structure made to resemble a natural cave.” The Grotto of the Redemption is really nine of these structures connected, each depicting a different aspect of the Old Testament or Christ’s life.

In 1912, Father Paul Dobberstein started crafting the grotto — concrete covered by a wide variety of rocks, petrified wood and other materials. Today, the grotto and grounds take up two city blocks.

Father Dobberstein’s work has drawn a lot of attention. As many as 50,000 people from all over the country and world visit the grotto annually.

The grotto is owned by the Diocese of Sioux City and is on the National Register of Historic Places. Efforts are under way to have it declared a diocesan shrine, according to Harry Bormann, grotto board president.

The grotto’s size and design are amazing, but at the same time, I couldn’t help but focus on the individual rocks arranged in patterns on all its surfaces. From calcite and rose quartz found in the Dakotas to agate, azurite, malachite, and many crystals, the grotto is a rock lover’s dream. There are precious stones and rocks from around the world, including many Father Dobberstein mined himself at U.S. locations.

But the grotto is more than rocks, which my friends were discovering.

The grotto dedicated to the Blessed Mother, with its beautiful dome, was the favorite of some among my group, as well as Bormann.

“If you’re having a bad day, you can go in there and look up; you’ll be better pretty quick,” he said.

Each unique grotto offers a place for contemplating a particular story or mystery, including the home of the Holy Family in Nazareth, Stations of the Cross, and Adam and Eve.

In front of a statue of Moses in the Ten Commandments grotto are stalactites from South Dakota.

The nearby church, Sts. Peter and Paul, contains the Christmas grotto depicting the Nativity with precious stones, including a 300-pound amethyst.

There are other grottos in the Midwest, some of them inspired by Father Dobberstein’s work, said Lisa Stone, of Preservation Services Inc. in Neshkoro, Wis., which is involved in preserving the grotto. The grotto is “an amazing amount of work and materials that were gathered, a really fine aesthetic that inspired so many builders and really contributed to a sensibility and a great collection of sites and environments throughout the upper Midwest,” she said.

The grotto is inspirational, Bormann said. “If you look at this and imagine that somebody put every piece of rock in there by hand, and if you look at the size and the scope of this and you think about how dedicated they were to building the grotto, it really makes you stop and think how good God is to you.”

Grotto board member Ethel Klepper agreed.

“It’s just a religious experience,” she said. “It’s handmade and something beautiful. There’s not another one like it any place in the world.”

The grotto is open all year. Visitors can take a 45-minute tour from May through mid-October and on weekends into November, depending on the weather. Larger group tours are available by appointment. A donation is suggested for tours.

Visiting the grotto, Rod and Kelli Jensen of Audubon, Iowa, noticed Father Dobberstein’s workmanship. “It’s just incredible the amount of time he put into it,” Rod said, adding that he was considering bringing his Methodist Sunday school class for help in explaining the faith.

My friends reminded me that our trip to the grotto had been a pilgrimage. With contemplation, Ann Lazor of St. Charles Borromeo in St. Anthony said, “You don’t see immediately what’s there, but spend time, and things pop out. The longer you’re there, you discover more depth and different layers of beauty and faith.”

Therese McCann of St. Joseph in West St. Paul said, “For a pilgrimage, it’s far enough that you’re going somewhere, but not too far that you can’t do it in one day.”

Pilgrimages to places like the grotto strengthen our faith, said Jenny Hirsch of Holy Family in St. Louis Park. “Each stone is like a prayer,” she said.

For more information, visit westbendgrotto.com. For tour availability, call (515) 887-2371.