GREEN BAY, Wis. (EWTN News) — Attendance is booming at a Wisconsin shrine at the site of the only approved Marian apparition in the United States.

On Dec. 8, 2010, the Solemnity of the Immaculate Conception, Bishop David Ricken of Green Bay decreed that the Virgin Mary had appeared to a young Belgian immigrant woman, Adele Brise, three times in October of 1859.

After that, shrine caretaker Karen Tipps said, “the phone was ringing off the hook.”

“Right from Dec. 8 on, we never had a slow time this winter,” she told the Green Bay Press Gazette.

People have come from as far away as Texas, New Orleans and the south Pacific island of Tahiti to pray at the chapel, located 17 miles northeast of Green Bay.

Tipps estimates that visits have increased from about 75 to 100 visitors a day to between 500 to 800, including daily bus tours.

“The turnout has been incredible,” Bishop Ricken told the Press Gazette. “It’s been a wonderful gift to the diocese. So many people are coming, and there are all kinds of reports of answered prayers and healings continuing.”

Interest could grow even more with an upcoming ABC Primetime Nightline show featuring the Shrine of Our Lady of Good Help (to air July 13 at 10pm Eastern. The episode includes an interview with Bishop Ricken and others who recount their experiences at the shrine).

In December, the bishop had declared with “moral certainty” that the 19th-century Marian apparitions were “worthy of belief.” He also confirmed the diocese’s official recognition of the popular shrine.

During each of the three apparitions, a lady in shining white clothes appeared to 28-year-old Brise. In the third appearance, she identified herself as “the Queen of Heaven who prays for the conversion of sinners.”

“I wish you to do the same,” the woman told her, who had intended to become a nun before coming to America.

The Virgin Mary gave her a mission of evangelism and catechesis on the American frontier: “Gather the children in this wild country, and teach them what they should know for salvation. … Go and fear nothing. I will help you.”

Brise went on to become a Third Order Franciscan and traveled throughout Wisconsin giving religious instruction at a time when the state severely lacked priests and churches.

A chapel and school were built at the site of the apparition.

The diocese has added staff, volunteers and amenities to the small chapel and 5.5-acre site. Officials are beginning to plan for future growth and possible expansion of the site. Two new priests from the Kentucky-based Fathers of Mercy will be on site daily.

Bishop Ricken said, “I think the biggest challenge is going to be keeping up with whatever the Blessed Mother does. However she chooses to use this place, we are going to be running to catch up most of the time. But what a pleasant problem to have.”