You can brave the line for a look at its interior and climb to the top of its bell tower. But the church I like to visit in Paris, especially on Sunday mornings, is St. Sulpice — to enjoy its magnificent pipe organ, arguably the greatest in Europe.

For organ lovers, a visit here is a pilgrimage. After Mass, enthusiasts from around the world scamper like 16th notes up the spiral stairs, into a world of 7,000 pipes.

Before electricity, it took three men, working out on these 18th-century Stairmasters, to fill the bellows, which powered the organ. The current organist, Daniel Roth, carries on the tradition of welcoming guests into the loft to see the organ in action.

As his apprentices pull and push the many stops that engage the symphony of pipes, a commotion of music lovers crowd around a tower of keyboards and watch the master at work.

St. Sulpice has a rich history with a line of 12 world-class organists going back over 300 years. Like kings or presidents, the lineage is charted on the wall. And overseeing all this? Johann Sebastian Bach.

This sacred music continues to fill the spiritual sails of St. Sulpice as it has for centuries.