Lots of brickwork on the outer walls, plus concrete work in the triangle lot.
Wednesday's weather was more March-like than mid-May-like, as BCB's David Sameshima found out when he visited Wrigley Field late in the afternoon:
I arrived just before 4:00 p.m. It was a still-chilly 45 degrees, with a 39 degree wind chill when I arrived. It actually got colder while I was there; my phone showed that it was 44 degrees with a 36 degree wind chill when I left. It also started drizzling shortly after I arrived. It never turned heavy, but came down steadily during my visit.