The Markthäuser on the Cathedral square.
You just can’t avoid them.
They either house the best record store in Mainz (used to any way) or they’re being knocked down and rebuilt or the city planners can’t sell the apartments they built or let the retail space they – in their infinite wisdom – put in the basement or they (the city planners) are in a clinch with the guy who runs the Figaro, one of the cafés. (He says “someone” told him he could have x number of chairs outside, the council reckons it’s x/3 and “nobody” told him anything different.
As in everything in Mainz, there’s a back-story
And see what the rest of the City Daily Photo blogswarm are doing today