It's impressive to think what it takes to keep a medieval basilica constantly ready for worship and tourism -- all over Europe and all through the ages. Churches everywhere have workshops associated with them, where statues gnawed bald by acidic air are redone, where soot-covered stained-glass windows are cleaned, and where precious mosaics -- ground down by centuries of footsteps -- are refreshed.
Here at St. Mark's Basilica in Venice, where mosaics are a big deal, they have a famous mosaics workshop. We visited to film the artisans at work. You'll see the complete, high-definition version in a beauty sequence in our new public television series. But this much more informal video (sorry about the jerky camera work) offers a peek at the working side of this thousand-year-old basilica.