Barcelona
Here's my philosophy on "travel guides" so read this to understand the randomness of what follows.
When I say that I am not a planner, I'm not being self-deprecating. But even for my lack of planning, Barcelona stands out as a destination that I really, really did not plan for. In fact, the entirety of my planning consisted of skimming some websites, getting distracted by the marvel that is Gaudi architecture, buying a book (or 3) on Gaudi, reading those books, and then later realizing that reading biographies of the city's most famous architect doesn't actually count as planning. Which led to me frantically skimming a few web-guides while in line at Disney World the week before we left. I did book one and only one thing in advance, and that was the Sagrada Familia, which thankfully the line for Tron was long enough that I had enough time to book tickets, because they did sell out. (I checked. I wanted to go back again, it was that incredible). Then we almost missed it anyway after we barely made it out of Belgium on the last flight before the transportation strikes began. Otherwise, my lack of planning worked out ok. We were there in the off season and saw everything we wanted to. We probably missed stuff that would have been interesting, but I didn’t know about it since I didn't plan and thus didn't miss it so I'm calling that a win.
Weather
We visited in the winter off season and it was fantastic. I know it's a beach destination in the summer and I'm sure that's amazing but we were perfectly happy with the 60 degree, jeans and sweater weather we experienced in November.
Food
Tapas, Tortillas, and Paella (need I say more)? Spain is an easy place to eat, we didn't do anything fancy and we didn't make any reservations. We just tried to step off the main tourist strips and duck onto side streets to look for whatever café or tapas bar caught our fancy.
The new Camp Nou
We really lucked out here, Camp Nou had just reopened after extended renovations and we managed to snag tickets. I love the energy of a city on game day, and Barcelona fans are amazing. Highly recommend making time for a game even if you aren't the biggest sports fan (I did have to keep asking my boys to explain the nuances of the game to me, and I still enjoyed it immensely).
The Picasso Museum
It has taken me plenty of years of begging bribing children to visit art museums, but we are finally at the point where when I mention visiting the whole family cheers. But even among my (now) art loving family and all of their various tastes and preferences when it comes to art, the Picasso Museum is a stand-out favorite. Pretty sure all 5 of us ranked it as being in our top 3 worldwide, and the Las Meninas exhibit alone is worth an hour of your time and the price of admission.
Getting Around
Weirdly, of everywhere we have been this was one of the harder cities to get around. The subway ended up being the easiest, and we probably should have tried that sooner. Ubers are almost non-existent, and using the Uber app to call a taxi was hit or miss. Our hotel concierge suggested using the local taxi apps, but we didn't have a ton of luck with those either (I suspect our new accounts didn't help). While there technically are Taxi vans that could fit all 5 of us, the wait was often 30 minutes or more, so we usually just called two cars instead. In the main areas of the city though it's very walkable and since it was perfect walking weather while we were there we definitely got our steps in.
Photographing
This city is all about the architecture so pack your wide angle lens. I had the M-11 with me so the widest lens I had was a 21mm prime. It worked fine although I could have gone wider. Narrower, even a little bit, would have been tough, so think 16/20 over a 24.
The Sagrada Familia If I could only ever see one thing in Barcelona this would be that one thing. Words, and photographs, don't do it justice. You will need to book tickets ahead of time!! We went in the off season and I just managed to get tickets the week before, so book early. I also don't know the best time to photograph this, its crowded no matter when you go. I could theorize that the first timeslot of the day might be a bit emptier since the time isn't limited so crowds might stack up. I avoided mid-day because I assumed that the light would be better coming through those stained glass windows on more of an angle than directly overhead. Mid-morning when I was there the light was coming through the warm-toned windows creating an amazing tunnel of yellowish-orange light. I suspect that in the later afternoon the cool-toned windows on the opposite side would create the color-casts. Really though, I can't image there is a bad time to see this.
Palau de la Musica Catalana This stained glass ceiling in the main music hall is jaw-dropping but walk through the whole space, there are plenty of amazing details. Of anywhere we went this is where I missed a wider angle lens the most- 21 felt a bit limiting although I think it did work.
Park Gruell This is the absolute most whimsical space and it feels like walking through a fairy tale. Our reservations were for late afternoon, I was aiming for golden-hour light. If I visit again, I'm going to try for morning instead, my guess is that the light will be almost as good but it might be less crowded.
Casa Balto This is another crowded spot with timed entry, but don't let that deter you. This is Gaudi's sea inspired masterpiece and its stunning. Again, I probably should have booked the first timeslot, I'm guessing that would have helped the crowds, but its amazing, incredible and worth the stop. I mostly used the 21mm, pausing as much as possible to avoid visitors (but admittedly it took come content-aware fill to rid the wide-angle images of visitors altogether), but a medium telephoto (24-70) would work well for detail shots.
Casa Mila The main attraction here is the chimneys so make sure you make it all the way to the rooftop. The house itself is lovely, not as whimsical on the interior as Casa Balto and extremely unassuming on the outside (unless you look up and catch site of those chimneys) tucked into a residential side street. I went mid-day because that's how my schedule worked out, and I'm happy with the chimney's against the Blue sky, but you might want to try earlier/later for more flattering light.
Markets I enjoy markets as much for the people watching and street photography as for the shopping, and Barcelona is no exception. If you are lucky enough to be there during the Christmas season, the Christmas markets tucked into the areas around the cathedral and the Sagrada Familia are lovely. They are not the huge affairs of many European Christmas markets but that also means lower crowds. They are festive and if you aren't already familiar with the Catalan tradition of Tito, you will be after visiting. If you aren't there during the Christmas season La Boqueria is right off of Las Ramblas, and it's worth the detour.
Montjuic Castle Make this a sunset stop, and take the cable car to the top. Situated along the shore, this is a stunning location and if the castle itself isn't enough to catch your photographic fancy, the views of Barcelona and the Mediterranean are a nice bonus.
Gothic Quarter I'm a bit of a flaneur, and I enjoyed exploring neighborhoods all over the city. But the gothic quarter, which is basically the area surrounding the cathedral are especially nice for photography (and exploring). One of the cities oldest neighborhoods, the medieval architecture and cobblestone streets are just incredible.
Note that all of the destinations on my photography list are worth visiting on their own, even if you don't bring a camera. If you're like me, photographing a place only adds to my appreciation and enjoyment, but most of these places are worth just experiencing for a few minutes. Stand in those colored patches of light in the Sagrada Familia. Imagine being under the sea while standing in the corridors of Casa Balto, and watch children play around the gingerbread-like structures of Park Gruell. Then photograph it.
I joke that my bucket list only gets longer, never shorter because I never actually check anything off the list. Visiting always makes me want to visit again. I would love to experience Barcelona in the summer, even though I'm glad I came for the first time in the fall. I would love to come back. I want to see more of Spain. And If I had just one more day I would have done a day trip to Andorra, so I'll be back to try that at some point as well.