Barcelona on Easter Sunday

Your activities as a visitor won't be hampered at all, as explained above. If you are looking for a church service then search out the Basilica of Santa Maria del Mar.

hahaha @billsinclair0.... I wouldn't have put it better myself. You're indeed right on the spot with Gaudí's intentions for Sagrada Família :))

@avirosemail, Easter in Catalonia -and specifically in Barcelona (you know, big cities are full of atheists :)- is not "that" religious. I'm not saying is not religious at all, but as @billsinclair0 said, nothing like in other shores. Having said that, two of the biggest cities in Catalonia: Tarragona and Girona have some fantastic shows/parades (excuse if I'm not using the 'correct' word whatever it is) during Easter that even if one's not religious are worth seeing. Some minor displays are held elsewhere, including Barcelona, in which Catholics practice their rituals and beliefs but it's far from being something major affecting/involving most. In reality Easter is for many yet another holiday and as such take the opportunity to escape the city. In Barcelona is pretty much like another Sunday, which means, shops are closed -except for small convenience stores, kiosks and bakeries- and most bars and restaurants are open as in any other Sunday. Museums and attractions are also business as usual.

If you're particularly interested in Easter religious celebrations, you might be interested in the procession of Verges, north of Barcelona (near Girona) which is famous for its Dansa de la Mort (“Dance of the Death” or “Macabre Dance”) celebrations every Holy Week, probably the last remaining Dance of Death in Europe, performed uninterruptedly since the Middle Ages.

This is good for me to learn; I was assuming, incorrectly it seems, that commercial activity would close down on Easter.
I thought I had noticed that there weren't any tours being offered by my favorite tour company, and it spooked me into thinking that I'd be stuck with nothing to do.
So, I'm hoping to find a walking tour to join on that Sunday, which I was worried wouldn't be possible on Easter.
I should also check the hours of the archaeology museum that you mentioned previously, Enric!

I have a special predilection for recommending RunnerBean tours as all my friends that have visited and used them, as well as the feedback from other visitors, has always been very favourable.

I second that suggestion to look at Runner Bean Walking Tours. I have taken them on a couple trips to Barcelona and I thought they were great - informative and entertainingly led. I have also taken a couple of the tours offered by the city's TI (located in Placa Catalunya), but I do not know if they operate on any Sunday, let alone Easter ...