From Cities Skylines experience it's usually to relieve traffic blocks by providing a direct path to areas/landmarks that have a higher than average traffic load. Not sure why they did it though.

[–] AngryCommieKender@lemmy.world 4 points 9 months ago (2 children)

That sounds like a reasonable explanation, but I'd have thought that Barcelona was laid out far before the advent of modern city planning.

[–] OlinOfTheHillPeople@lemmy.world 10 points 9 months ago* (last edited 9 months ago)

This part of Barcelona pretty much was the advent of modern city planning.

https://en.m.wikipedia.org/wiki/Ildefons_Cerd%C3%A0

[–] GissaMittJobb@lemmy.ml 4 points 9 months ago

Eixample was built in the mid-1800s iirc, and they did put some thought into its construction.

[–] Buddahriffic@lemmy.world 8 points 9 months ago

I can't tell if they are actual streets, pedestrian-only areas, or bus loading/unloading zones. There look to be structures along them that could be market booths or buses.

That's if you mean the two blocks with the diagonals going through them. If you mean the one in the back that's slightly off-angle from the grid, my guess for that is that the road existed before the modern city did and wasn't removed to create the grid. Or it might be a rail line.