Thanks to BVG’s U5 extension project, Unter den Linden (is this Europe’s most lovely street name?) is currently peppered with hoardings, pipes, tanks, temporary pedestrian sanctuaries, temporary traffic barriers and all manner of other markers of ongoing construction. In addition, many buildings along the grand boulevard seem to be undergoing winter facelifts, and so are shielded by great walls of scaffolding and modesty wraps printed with their own likenesses. The impression, then, as we walked from Französische Straße past Bebelplatz and on towards Museum Island, was of a city partially cocooned. The metamorphosis that this ‘cocoon’ implies is at the heart of what makes great cities sublime – constant change, for better or for worse, in all quarters visible and invisible.