I visited Barcelona in 1982 and then again, 20 years later, in 2002. I am certainly glad I read Robert Hughes' "Barcelona" before going the second time since it certainly gave me a new perspective on the city, its history, its art, and its architecture.
The history of the Catalunya area is fascinating, an area that predates the Roman Empire. Two Roman Emperors came from Barcelona, Trajan and his nephew Hadrian. Hughes helps us understand the unique development of the Catalan language, culture, history which is frequently at odds with Madrid and Spain's central government.
Hughes does an excellent job of mapping the development of city with changes in politics and the coming of the industrial revolution. At one point, Barcelona was filled with sweat shops, offering long 12 hour days, very low wages, unhealthy nasty work conditions, deprivation of exercise and light, and explotative child labor. As I walked the city of Barceona, I imagined the struggling families trying to survive under these conditions in times past.
Even though the full 574 pages are engaging in this long book, the chapters on Gaudi are the strongest, most enjoyable, and most insightful. If pressed for time before taking a tripto Spain, I would strongly recommend reading the sections on Gaudi before seeing his actual works which are spread out all over the city of Barcelona.
The concept that was fascinating to me was Hughes' explanation that Gaudi's work was in fact very conservative rather than radical. His work is based on a return to the natural object, the shell,the wing, the tail, the spine, the leaf, the root. His work takes these natural objects and reduces to essential form and then expands again from that essential form with texture, color, and sensitivity to the material and physicality of the medium. This explains the amazing popularity among the Japanese for the work of Gaudi, which philosophically and esthetically is more in line with Japanese culture and esthetics. Knowing this before seeing his Cathedral, parks, and residences gave me a completely new appreciation for Gaudi and the city in which he created his masterpieces.