Mass in Chapels


Hi all-

I recently made a trip to the National Shrine of the Immaculate Conception in DC- great trip and beautiful church, btw- and a question crossed my mind that I forgot to ask at the Shrine.

In large Churches and Basilicas I’ve visited (in the USA, at least), there tend to be many smaller “chapels” with altars on the sides of the main sanctuary. Specifically in the National Shrine of the Immaculate Conception, the Basilica of the National Shrine of the Assumption of the Blessed Virgin Mary in Baltimore, and the Cathedral Basilica of Sts. Peter and Paul in Philly- all of these churches have these side altars, generally with images of Our Lady or a Saint, and always with a crucifix.

These altars have been “dedicated,” I’ve learned, but my main question is: Have masses been said and are they commonly said on these altars and in these chapels?

Does anyone have any idea?


I was visiting a seminary which had the same type of thing. I was told pre VII (before con celebration) a Priest would use the side altar to say his mass for the day.

Not sure if that is what those altars are for, but it would be my guess.


I remember back in those days that if a Catholic married a Protestant, it often was performed at one of the side altars in the Church–back then almost all the older churches had them. There was no Mass, just the ceremony.



For the National Basilica at Catholic U. The different chapels are used frequently. Each one is different, though. Many of them were donated by particular “groups” such as a diocese or religious order. When those groups visit, they will typically use that particular altar. They don’t have a set program for using them (like rotating clockwise, once altar each day).

I can’t speak for the other large churches directly, but as a general rule most of them are used from time to time–that is, if they are still altars, and have not been relegated to being merely ornate flower stands (which I personally think is a shame). If there’s a statue or something placed directly onto the altar, then you know it’s not used as an altar anymore. One can usually look around for some obvious signs that it gets used occasionally, like candles on the alter that look like they get used as opposed to being just decorative, or a missal nearby.

I know of one basilica that has about 8 side altars but uses 2 of them (occasionally).

There’s just no single answer that applies to all the altars at all the big cathedrals/basilicas. Some are used, some are not. It all depends.


Thank you very much for your answers. That clears up the question. I have another question somewhat related- when altars have relics interred into them, how are the relics commonly put in? Are the altars hollow or are the relics set in the stone, or could you see them if you lifted up the altar cloth? Just a question I’ve had.


In regards to the Cathedral Basilica of Sts. Peter and Paul, the side altars, along the wall in the nave are not used anymore. Most still have tabernacles, but the relics were removed, and approx 2 were upgraded into shrines by Cardinal Rigali, but lost their tabernacles.

The two side altars, parallel with the main altar are rarely used, while the large daily mass Chapel (which is the size of an average parish church) is used every day.

Before VII, the Cathedral used to have approx 10 priests, but today only 3.


It’s also my understanding that before Vat. II and the common practice of concelebration, it wouldn’t have been unusual to see several priests simultaneously celebrating private Masses at side altars in these large churches.


Again, it all depends.

Some large churches (cathedrals, basilicas) have rather large relics of saints placed into “niches” below the mensas.

Obtaining large relics of martyrs is not always easy. Custodians of shrines tend to be rather reluctant to just give them away, and keeping them there is their job.

I think that the most common way of doing things in the past (many modern churches don’t even bother with relics of any kind----I’m sad to say) was to have an altar stone (say roughly 12 inches square) which was cut from natural stone and then had a small hole hollowed-out (about the size of a quarter). A small piece of a martyr’s relics was placed in there and then the hole was closed with some kind of masonry or a very hard red wax. I’ve seen a lot of altar stones over the years and they all seem to follow that pattern.

Here’s a pic of the altar of Sacred Heart Basilica, Notre Dame:

Look carefully below the table. There are what look like 2 red velvet pillows. They are actually the bones of martyrs covered in red velvet.

That’s not typical of a parish church, of course.


It’s been almost 1 year since I’ve visited there, and it’s so beautiful. I’m glad you went and enjoyed it!

What was your favorite part? I spent the whole day there, including Confession, followed by Rosary, then Mass (complete with the organ and all!), then visiting all of the main floor and the gift shops. Also met the fabulous lady who works in the office, and purchased some eternal novenas. So, so amazing. Wish I could be there to see the Pope!


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