Hexagons were a popular shape, and the Spanish have perfected them in large-format, super thin, super strong ceramic tile. This wall demonstrates a tile intended to sheath whole buildings.
When used on the exterior of a building like this, tile isn't held in place with mastic and grout. Rather, it's hung on a metal rack with a layer of insulation behind it. The term for this is a ventilated wall, and it makes for a very energy-efficient building.