Can I ditch the Jeans in holy places?

In St. Peter’s, the Sistine Chapel, St. Marks, and the Pantheon, you risk being excluded if your knees and shoulders are not covered. In the Forum, no restrictions as I remember.

You will not be admitted to San Marco Basilica either. We saw a very disappointed young woman in a sleeveless top turned away. No one in line wore shorts but I am sure they would have been refused as well.

How about a knee-length skirt, or capris like these, which are nice and cool?

https://www.mountainhardwear.com/p/womens-dynama%2F2-capri-1880751.html

They can usually be found on sale on Amazon, but those links are too long to post.

Ditto to the above: I wouldn't risk it even if you DO see pix of visitors in some of these places who got away with shorts or sleeveless shirts. To be safe (and respectful) go with capris or a skirt that covers the knee, if you're a skirt person. No bared midriffs, please. There's no issue with shorts in the Colosseum, Forum or Palatine 'cuz they're not religious institutions. The dress rules generally apply to all active Catholic churches in Italy.

This on the Vatican Museum website:
"Entry to the Vatican Museums, the Sistine Chapel, St. Peter's Basilica and the Vatican Gardens is permitted only to appropriately dressed visitors. Sleeveless and / or low-cut garments, shorts above the knee, miniskirts and hats are not permitted. The requirement of decorum extends also to any visible personal objects as well as similarly visible distinctive personal signs (such as, for example, tattoos) that may offend Catholic morality, the Catholic religion and common decency."
https://www.museivaticani.va/content/museivaticani/en/organizza-visita/consigli-utili.html

The same rules of dress didn't apply to the Sistine's ceiling. (wink, wink)

My two cents. It's good manners. From a tourist's perspective, sources often describe what you can get away with rather than what is respectful to the people there. From a worshipper's perspective, respect beats personal comfort.

Why the quotes around "the rules"? Yes, those are the rules for entry into holy sites in Italy. It is also a sign of respect for the customs and traditions of those places. Failure to comply means you will be denied entry. Period.

Surely you are aware that there are acceptable (and comfortable) alternatives to either jeans or shorts. And I'm not sure why anyone would pack jeans when going to a place they know will be hot. If you are male, then pack lightweight, breathable trousers in cotton or linen. Or get some of those convertible trousers that zip off to become shorts. Or go for the male Capri equivalent. Keep your shoulders covered with short sleeved shirts or t shirts. If you are female, wear anything that covers your shoulders and knees. A below knee dress with sleeves. A sleeved blouse or t shirt with a below knee skirt, Capri, or slacks in a lightweight, breathable fabric. It's not rocket science. Besides, covering yourself in the appropriate clothing keeps the sun off your skin. Your dermatologist will approve.

My wife uses a light pareo or scarf to wrap around her waist over her shorts. Then when we are done, she removes it, folds it, and puts it in her purse. Works like magic.

Did you feel pressured to cover up if you weren't dressed according to the "rules"?

People generally adhere to the cultural and religious requirements of the places they visit. Rules are not “rules”. Requirements are not “pressure”.

Thanks everyone for the replies! I completely understand the sanctity and importance of religious sites. Coming from India, I wouldn't dream of disrespecting a temple's dress code, and the same goes for these holy places in Europe.
I think the question came with packing light as a goal, and that's why I was wondering if shorts might be okay. However, I hear you all loud and clear about the dress code, and I wouldn't want to be turned away.
Pareo and linen pants are great suggestion, and i had already packed some linen ones for me and DH, for the kids I'll will figure out something appropriate, will look for those convertible pants!

We travel in Italy during the summer heat frequently. Linen and lightweight cotton are what we do--breathable fabrics.

Shorts are fine --- IF THEY COVER THE KNEES. But, I suppose, if they cover the knees -- then they are no longer shorts? We haven't had this discussion in a long t ime but basically it is call --- respect. Most of the churches are fully functioning religious organizations that just happen to be open for visits by tourist.

In Florence last year two girls ahead of us in line were not permitted to enter the baptistry wearing shorts. I was worried because my husband had long shorts on but was allowed to enter.

I was in Florence recently and the Basilica of Santo Spirito was open. I had never been in so went in. There was a woman denying entrance to people to go into the body of the Basilica. Two women that came in after me were denied. I had on a dress that covered my knees, but it was sleeveless. I opted not to try. However, they did have cover ups available to purchase for a small amount. I didn’t even have the change to be able to, but it may be an option provided if for some reason you find yourself wanting to go into a religious site and didn’t plan accordingly to see that particular one.
Then retain the coverup for the next time should it arise.

When you're traveling in the summer and wilting from the heat, popping into a nice, cool church with thick stone walls is a very attractive proposition. I always dress so I can do that whenever I want to. I keep a headscarf in my purse so I can legitimately enter mosques and orthodox churches, too.

When we were in Vietnam recently, we were at a Buddhist temple that provided cloth wraps at the entrance for those who were wearing shorts. You just put it around yourself and tied it off to walk in. For free. It was certainly convenient. Granted, in Europe they maybe wouldn't have this type of clothing for the legs.

There is somewhat of a double standard when it comes to this. As a male (and one who lived in Rome and traveled extensively throughout the country and just returned), I can tell you that there is more leniency for men whose shorts come to just above the knee (but not short shorts like running shorts) than there is for women whose shoulders are not covered. Out of respect, I always opt for the more conservative approach.

It’s been years but my sister was denied entry into St. Mark’s because her shoulders weren’t covered ( it was July !) so she wore a dress with sleeves to St.. Peter’s. Oops ! above the knee so she was yanked out of line by a little nun. I think that was the nun that was mentioned in an article who suffered from exhaustion that summer keeping people out. She spent the time I was in the church talking to two girls we had met a week earlier in Salzburg. They even ripped their dress hems in a futile effort to get the dress below the knee.