A look inside one of Mexico's most historic Catholic churches

MEXICO CITY (KABC) -- During Pope Francis' visit to Mexico City, ABC7's David Ono encounters one of the oldest Catholic churches in Mexico that helps highlight how deeply ingrained the Catholic religion is in the country.

Built in 1485, the Santa Maria de la Natividad was already 300 years old when our founding fathers were just forming the United States.

Father Arturo Escavel Deleon and Sergio Silva said they were renovating the original bell tower and other parts of the building.

It began as a Franciscan convent, and centuries ago, it was a common stopping place for Spaniards to water and feed their horses.

Inside the modest chapel, there is a carving of Christ on a cross that was made by hand in the 1700s.

Although it may be a small place of worship, it supports many followers. On any given Sunday, 1,000 people attend Mass. On major religious events such as Easter, the chapel is filled with 1,500 attendees.

Residents said part of the renovation is so the overflow of people can spill out to the courtyard.

There is no country in the world that has a higher percentage of Catholics, and going into such a historic place helps explain why that is.