Palau Güell is lit from the middle, because it has almost no outside wall to open. Eusebi Güell bought a plot on a narrow lane in the Raval, with a frontage of eighteen metres and neighbours pressed against three sides. Gaudí answered it by cutting a hall three storeys high through the centre of the house. Its parabolic dome is pierced with small round holes, and from the floor at midday the ceiling reads as a sky full of points of light.
The family chapel folded out of one wall of that room, and an organ plays down into it. Güell had made his money in textiles and cement. In the 1880s Barcelona's rich were moving out to the new grid of the Eixample, but he wanted his house next to the one his family already owned, so he built here instead. What he was buying was a palace address in a quarter that was already poor. The house closed for seven years of repair and opened again in 2011.