And rightly so. It’s the most popular Catholic shrine in the world. Some 20 million people visit each year.

What most don’t know is that, in the wake of Juan Diego’s image-producing encounter with the Blessed Mother in the 1500s, there came an effusion of Marian devotion throughout the country. Millions converted to the Catholic faith — and hundreds of churches and shrines were built. Many of these “secondary” sites are familiar to Mexicans but unknown to Americans.

Last fall, having heard about this great but unheralded treasure trove, my husband and I embarked on a six-week bus tour of Mary’s Mexico. May being the Blessed Mother’s month, now is a good time to tell what we found.

First things first. In our travels, we discovered not only a plethora of these wonders — we visited at least 20 unforgettable shrines — but also the excellence of the Mexican bus system. Contrary to popular perception, it was efficient, luxurious and inexpensive. We were even served lunch.

Now to the shrines. All the sites we visited have been approved by the Church, most have fascinating stories to tell and many are thronged by pilgrims. The Miami Herald reported that 1 million pilgrims turned out for the Oct. 12, 2005, feast of Our Lady of Zapopan, a shrine near Guadalajara. Pope John Paul II visited several of these shrines and churches during his five trips to Mexico.

The shrines are open all day and have evening as well as daytime Masses. Many also have Eucharistic adoration.

It would be impossible to single out favorites, and this space is limited. So here are descriptions of three of Mexico’s lesser-known Marian shrines that hint at the immense spiritual riches south of the border.

_{Carved Compassion}

A short ride from the Zocalo (the main plaza) of Mexico City is the remarkable Church of La Piedad (Our Lady of Compassion), connected with the Dominican convent of La Piedad founded in 1595.

Placed over the main altar of this modern yet reverent church is a 400-year-old image of the Pietà. Its origins were miraculous. Two Dominican friars journeyed to Rome to commission a painting for the new convent. Instead of a work of art, the disappointed pair returned to Mexico with a barely finished charcoal sketch. This image of Our Lady was credited with saving their lives during a fierce storm on the voyage home.

As the friars were uncrating the “sketch” in the presence of their confreres, an exquisite full-color painting was revealed in its place. Many verified miracles have been worked through the intercession of Our Lady of Compassion.

The second most popular shrine in Mexico is Our Lady of San Juan de los Lagos, located in the town of the same name.

A reported 9 million pilgrims travel here every year. This bustling market town is a two-hour bus trip east of Guadalajara. The imposing 17th-century Franciscan cathedral with its splendid yellow-and-blue-tiled dome has a sumptuous interior; the sacristy is said to contain six paintings by the Flemish master, Rubens.

The events of this shrine began with a tragedy in 1623. A little girl, a member of an aerial acrobatic family, fell to her death while she was swinging on a trapeze high above the crowds. She had been dead for several hours when a devout lady suggested placing a statue of Our Lady on her chest. As soon as the image came in contact with the child, she sat bolt upright in perfect health, wondering what all the fuss was about.

News of the miracle spread like wildfire and crowds have been flocking to the shrine ever since, enamored of Our Lady of San Juan de los Lagos. They weren’t the only ones. When Pope John Paul visited the shrine in 1990, he lingered for long moments before the image of Our Lady; onlookers said he bore an expression of “intense recollection” and seemed reluctant to leave her presence.

_{Song From the Wood}

Tlaxcala, a picturesque town in the highlands of the Sierra Madre Oriental Mountains, is home to one of the loveliest churches in all of Mexico: Our Lady of Ocotlan. British writer and art critic Sacheverell Sitwell described it as the “most delicious building in the world.” It is reached by a scenic 90-minute bus ride from Mexico City’s bus station, or a half-hour bus trip from the city of Puebla.

The basilica is in the Churrigueresque style, a type of architecture named after the 17th-century architect, Churriguera, who was known for his ornate, Baroque style of decoration.

The miraculous events associated with this shrine are as extraordinary as those of Guadalupe. It’s said that, in 1541, Our Lady appeared to a humble Indian and revealed to him a spring of water that would heal the entire town of smallpox. (At that time 9 out of 10 Indians were dying from the disease.) She also had a message for the Franciscan friars. They were to find an image of her “in this place” through which her “mercy and blessings would be brought forth.”

Taking an ax to the tallest tree, the astonished Franciscans discovered the beautiful, 5-foot-high statue of Our Lady of Ocotlan encased within the trunk of the tree. This image is situated over the main altar of the basilica.

She continues to bestow miracles to the present day. Bishop Escobar, ordinary of the Diocese of Tlaxcala, witnessed a miraculous change in the statue’s facial coloring in 1987. This is a phenomenon many have noticed throughout the ages.

Back in 1958, Joseph Cassidy wrote a book about the shrines of Mexico. He called it Mexico: The Land of Mary’s Wonders. Although the book has long been out of print, its premise is as good as new: For those with eyes to see, Mexico is indeed both Marian and wonderful.

Mary Hansen writes from

Barrie, Ontario.