It is in a continual state of cosntruction that started in 1882 and will not be finished until at leat 2030, so do not think of it as a traditional church. It can dusty and you can ascend into certain spires. There are hordes of people including construction workers and architects.

I'm planning my first trip to Barcelona and the Runnerbean tour site states that you must cover shoulders and knees if you want to visit the cathedral cloister on their tour. I would think this would apply to other churches as well.

The Sagrada Familia is not complete but it was consecrated in November, 2010 so it's considered a church and not simply a building that will be a church one day. I would expect church rules apply.

You should bring more than sundresses since it can get cool at night. The 20 year average low temp for September is 62 and without sun that would be too cold for sundresses.

A lightweight open weave sweater or shrug, or a large scarf, would work as a cover-up in churches or wherever it might be a bit cool. Taking clothing for only one specific weather situation isn't very smart, whatever the season or activity.

The days of strict dress are gone! Once in a while there's a feeble attempt but I've never seen anyone turned away!
In Madrid I am always surprised at the state of undress in the churches!

Spain isn't Italy.

They do have services there, I think, but I do not recall any kind of dress code and I've never seen that in any church in Spain, anyway. People were wearing about anything. I have never heard of any rule about no bare shoulders there, I suspect there isn't any such rule in church in Spain for any reason. There isn't in France, I know that for sure, and I'm not even talking about tourists, I've seen local women with bare shoulders in French masses (eg, sundresses). Italy has all kinds of unusual rules, as they aren't even referring to "
shoulders" but include your upper arm. They don't have morals police at the door, it's a major tourist site, people sell tickets in booths, just clerks.

If you go on their website, they even have a photo of a woman in shorts in the section on visitors. Their website says their rules are that you should be dressed with "decorum", which means I suppose if you were naked or wearing a bikini, they might not let you in.

Looks like you can wear what you want but I've frozen inside stone churches even when it was hot outside.

My daughter was denied entry to the Catedral de la Seu a few years ago. We had just arrived in Barcelona and we dashed out without something to cover her shoulders. She was wearing a sundress with spaghetti straps. I was so mad at myself because I knew better.

Hi J,

Bring a large scarf.

Enjoy your visit.

i tend to wear a "tank" type t-shirt with a loose blouse/shirt over the top.

if I want to go in a church or it gets a little chilly i can put it on, if not, i can tie it round my waist.

SF will be one big mob scene if history is any example and you will almost undoubtedly see all sorts of dress modes. Being prepared to show the respect expected (even if it seems nobody else is doing so) might be your best plan.

we were lucky enough to visit the Sagrada familia at a time when there relatively few other visitors. even so we were not that impressed, and after 30 mins or so, made our excuses and left, unlike friends of hours who were there for 2 hours or so and still felt they didn't see enough.

so be prepared to be under, or over-whelmed.

The solution, even for a hot day, is a sundres and simply carry a gauzy lightweight over sized scarf to wrap around shoulders shawl style if needed. Easy to carry,I usually just tie it onto my purse when not in use.

Ps.. I was underwhelmed,, its all personal tastes, and what you have seen before to compare it to.

If you plan to go down from tower to the ground level, you will go thru endless steep spiral stair cases. You might want to choose dress and shoes suitable for such descent. There are many videos of people doing this in youtube.