Gaudi had a brilliant idea: “I’ll build a community.” Well, he thought it was a brilliant idea. It never really took off as a community. Only two homes were ever built.
Now Park Guell is a major tourist attraction.
Notice that there are many levels. Columns shelter what is meant to be a refreshing, shaded marketplace for the community.
Those same columns support an upper-level gathering place. If you look closely at the above picture, people taking in the view from the courtyard are visible above the columns.
Mosaics are everywhere, especially on the grand staircase.
Fine gravel covers the upper courtyard.
View of the community entrance and the city beyond from that upper courtyard
Covered sidewalks like nothing ever seen before.
Gardens and walking paths 
If planning a tour to Park Guell, reserve your entrance time in advance. Entrance is capacity controlled and it tends to operate at capacity. If you miss your entrance time, chances are very likely that you will be denied entrance.
After our tour, we walked around the neighboring streets and purchased three souvenirs: a T-shirt, a mosaic refrigerator magnet, and my required postcard.
Also, learn from my mistake. We purchased an additional day of Hop-on-Hop-off as our transportation for the day. We would have been better off with a taxi. Signage is confusing from the drop off point, and valuable time was taken just to get there. We arrived at our assigned time with only 3 minutes to spare. Once admitted, though, you can stay as long as you wish. Metro stops are not convenient for this destination, either.
Next post: Castle Montjuic