We spent the night in Lourdes for the 4th of July. It's a popular pilgrimage site that has become very touristy with tons of shops selling candles, rosaries, and bottles you can use to collect the holy water. And at night it all gets lit up with neon lights. 
If you can put the tourism aside though it is really an impressive complex with so many diverse chapels and churches in such a small place. You can give confession in at least 6 different languages and people come from all over to heal themselves.
Every night at 9 they have a short mass procession with candles. It was a rainy evening and still so many people showed up for it. I can't imagine how many people must visit this place each year if there were so many for just an ordinary day!
We weren't expecting to have the town fetes too. After the mass we walked through the neon lit tourist streets to the carnival and outdoor concert that was set up for the Lourdes festival. We waited for the main act to take the stage - Willy William. He sang Happy Birthday, which was cool since it was the 4th of July. Happy birthday USA! 