Observing the Shabbat rules doesn't have always to stop you from visiting a beautiful town as Barcelona. It just requires a bit more planning than usual and of course some more walking, but a good local guide can help making things much easier for you!
Yesterday I was with the Applbaum group and I took them to the Montjuic Hill. We had carefully planned all of our itinerary and needs beforehand. They had already purchased in advance their Articket cards (which I'd be carrying) to avoid using money for entrance fees and I had pocket money to provide water during the tour.
From their hotel conveniently located within walking distance from one of the city synagogues, we walked down to Plaça Espanya, then uphill to the MNAC Museum. It's a gorgeous place and its collection is huge, so we decided we'd be focusing on the upper floor where the modernist paintings are. The Romanesque section is closed for refurbishment until June anyway, and they had already seen enough Gothic art during the rest of their trip. They were amazed to see the high quality of our local 18th hundred artists!
After that, we crossed some pretty gardens and continued uphill to the Montjuïc Castle. We enjoyed the city views from there, freshened up and let the kids play with the canons for a while.
On the way down, I showed them the field where the Jewish Cemetery had once been in the Middle Ages and told them a bit about our Jewish History. Unfortunately, nowadays there is nothing to be seen in this place as some tombstones are now in museums or embeded as part of medieval buildings and the rest is buried, waiting to see if our City Council and the modern Jewish community agree on a respectful project to honour the place.
We also had a short stop at the Olympic Stadium, then walked back to the hotel passing the MNAC and Plaça Espanya, the same way we came.
We spent a total of 6h for the whole tour (but it could have been less, because we were a bit late departing the hotel when we started).
I am born a Christian (although I don't really practice), so I don't know the Jewish traditions and rules in depth, but thanks to my job I'm getting familiar with Shabbat habits and it's a pleasure for me accomodating to my clients needs and helping them get the best Barcelona experience they can!