The cityscape swings from majestic to quirky to rundown and back again. Art deco facades face off against 1960s concrete developments, and regal 19th-century mansions contrast with the shimmering glass of the EU’s Gotham City. This whole maelstrom swirls out from Brussels’ medieval core, where the Grand Place is surely one of the world’s most beautiful squares. But Brussels' greatest architectural expression came at the turn of the 19th century with art nouveau, and its master builder is Horta. While restraint characterises his exteriors, the interiors are sensual symphonies of form and colour.