Hundreds of Catholics in the Rio Grande Valley are expected to celebrate the Feast of Our Lady of Guadalupe.

The Basilica Of Our Lady of San Juan del Valle opened its doors at 6 a.m.on Friday. Overnight, faithful brought dozens of flowers and candles to the Virgin Mary.

Our Lady of Guadalupe is known as the Queen of Mexico and Patroness of the Americas; a title she was given by Pope John Paul II in 1999.

Officials said this is the most attended celebration of the year. The first mass was held at midnight and featured a mariachi singing Las Mañanitas.

Rector of the Basilica Father Jorge Gomez says they're expecting thousands of visitors throughout the day.

"It is a cultural and religious feast. It is by far the most well attended mass throughout the year at midnight tonight. So we have probably more than 3,000 people," Gomez said.

Another mass in Spanish was held at 6:30 a.m. Father Gomez says they expect the altar to be full of roses.

The Virgin Mary appeared to Saint Juan Diego on a hill in Mexico City, asking him to tell a bishop to build a church.

When the bishop asked for a sign, it came in the form of roses in the middle of winter and were put on Juan Diego's cloak.

Catholic leaders say the feast is all about community and prayer.

"It brings people together, because I think that's the message of Guadalupe, harmony and love and unity, which is what we need in our world today. In a very polarized world, we need unity, and that's the message she brings," Gomez said.

The basilica will hold three more masses on Friday. Masses scheduled at 11:30 a.m. and 5:30 p.m. will be bilingual, and a Spanish mass will be held at 7 p.m.

Attendees are asked to arrive early and follow traffic instructions from San Juan police.

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