The first stones were laid on the Catedral Metropolitana in the 16C, but construction wasn't completed until the early 19C, resulting in a plethora of styles including Renaissance (domes), Baroque (retables), Neoclassical (façade) and churrigueresque, illustrated in the most dazzling fashion by the Altar of Kings (behind the high altar, 1737). And while this monumental building may seem to be leaning a bit, rest assured, the worst is over. Although built on marshy ground, major reconstruction work has been undertaken to stabilise it.