Pittsburghers call it “cobblestone,” although real cobblestones are irregular roundish rocks, much harder to drive on than Belgian block. As a pavement, Belgian block is just about ideal for neighborhood streets. It lasts almost forever, it’s attractive, and it slows traffic to a safe pace on a residential street. Since most people think the object of driving is to go as fast as possible, most people hate Belgian block, and more and more Belgian-block pavements are disappearing under smooth asphalt. But there are still hundreds of Belgian-block streets in Pittsburgh and the inner suburbs.
In neighborhoods like Brookline, cheaper brick pavements were used on flat stretches of street. The more expensive Belgian block was reserved for hills, where it gives far better traction in wet weather than brick does.