SAN ANTONIO — Throughout Mexico and many Mexican-American communities around the U.S., today is the biggest day of the year for Our Lady of Guadalupe devotees.

Dec. 12 is known as her feast day and Holy Day of Obligation.

The tradition began in December 1531 after an apparition of the Virgin Mary revealed herself to Juan Diego, a Catholic convert.

In Catholic communities, the lady will be remembered today with special Masses and pilgrimages.

At Centro Cultural Aztlan in San Antonio, later this evening, some 25 artists will present the 22nd annual Celebración a la Virgen de Guadalupe Exhibit.  The free event will give visitors a chance to better understand the significance of the Latin American icon.

This exhibition is the longest running and most respected of La Virgen de Guadalupe as the central theme. Her image will be on display on canvas as well as just about anything you can imagine...

"It's in pillows, it's in jewelry, it's in clothing, it's in purses... so they'll get to see a variety of interpretations of La Virgen," said Malena Gonzalez-Cid.

Also today, devotees will walk a 17-mile pilgrimage between the two Our Lady of Guadalupe churches in San Antonio.

The 29th annual march begins at Our Lady of Guadalupe Shrine on the West Side and will wrap at Our Lady of Guadalupe Catholic Church in Helotes — just in time for the 6:30 p.m. Mass.