By John McDevitt

PHILADELPHIA (CBS) — Today is the start of World Meeting of Families Conference at the Pennsylvania Convention Center. Daily Mass will be held on each of the four days in halls “D” and “E” which have been transformed into a church.

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There is room to seat approximately 12,000 people for Mass.

“Right now, we are looking at the main stage. The contingency from the Vatican absolutely loved the fact that we could put the main stage on this wall,” said Peter Horch, director of events at the Pennsylvania Convention Center, “and then behind you you can see what guests will be looking at as natural night falls through our Broad Street atrium.”

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And on the windows of that atrium is a stain glass window effect. It’s 105 feet tall and 20 feet wide. The colors in the window cling are pale orange, yellow, light blue and white.

“This is the first time we have ever had something of this magnitude done in the building,” Horch says, “and the first time that we ever had a window cling put on the windows of the Broad Street entrance.”

And for those who want to go to confession before Mass — areas have been set up for that.

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