Which attraction should not be missed.

I m definitely going to Sagrada and part Guell that's why I asked about other attraction to have an idea to choose from.

I m definitely going to Sagrada and part Guell that's why I asked about other attraction to have an idea to choose from.

In addition to your picks, we enjoyed a free walking tour of the Gothic area and Gaudi with runnerbeantours..com. We reserved this online.

We took a guided tour of Palau de la Musica Catalana. Or even better reserve tickets for a concert in this beautiful concert hall.

We took the Hop on Hop off bus our first day. This gave us a good feel of the city. One of our favorite stops was at the Joan Miro Museum. Don't miss a great view from the top of El Corte Ingles Department Store while enjoying dinner.

We admired Casa Mila and Casa Batilo' from the outside with Runnerbean. We purchased tickets online for the Sagrada and Tower. It was the highlight of our tour of Barcelona!

From the standpoint of someone who enjoys art but is not a special fan of either Picasso or Miro, I found the Miro museum much, much easier to enjoy because it was not crowded. The Picasso often has so many people packed inside it that you can barely move. I am not exaggerating. I would choose MNAC over either of these, but it is much larger, so you may need to pick and choose due to your limited time available. It has a good modernism collection (furniture and decorative art) and some lovely frescoes that were removed (to protect them) from churches in the Pyrenees. Plus traditional things like paintings and sculptures. When I visited, there wasn't a significant ticket-buying line.

I would prioritize La Sagrada Familia. It's as close as I'll come to saying something is a must-see. You'll need to buy the ticket ahead of time to avoid a long line. I'd buy the first time slot of the day if it's available.

Casa Amatller is not really modernist on the inside and was less interesting to me than CasaMila and Casa Batllo. Folks who get tired of the modernist stuff might find Casa Amatller a welcome change. As far as I know, you don't have to buy advance tickets to C.A., but I was in Barcelona in 2016 and things may have changed. With limited time, I would definitely skip Casa Amatller unless you want to see a pseudo-castle-style interior.

Although I enjoyed Palau Guell, I didn't think it was quite as interesting as Casa Mila and Casa Batllo, so I'd skip it as well. The exterior is, to me, somewhat less distinctive than some other modernist buildings, so I wouldn't worry if you don't have time to walk past it. There are some modernist buildings scattered around the Eixample (marked on the 1-euro map sold by the tourist office, and perhaps on others) that I thought were more arresting.

During my visit Casa Batllo was marginally more crowded than Casa Mila, but they were both packed, so I'm not sure that makes too much difference. You definitely need to already have a ticket in your hand when you walk up to either of those places. Figure that you'll need at least 90 minutes in either one, once you get in the door. You may have a bit of a wait even with a pre-purchased ticket. I think they count people as they leave to be sure they don't exceed a fire-code limit (or something like that).

As of 2016 Barcelona Cathedral was free for part of the day but had a modest entry fee later on. I think the free time was in the AM. I doubt that you need to buy a ticket in advance, but cannot promise that there will be no delay. Barcelona is swamped with tourists.