Centro Galego de Arte Contemporánea, usually shortened to CGAC, is Santiago's sharpest break from granite cloisters and pilgrim ritual. The museum stands beside the Convent of San Domingos de Bonaval and Bonaval Park, but the building itself is modern, restrained, and very deliberately composed by Portuguese architect Álvaro Siza.
The exhibitions focus on contemporary Galician and international art, so the visit depends on what is showing, but the building is worth attention in its own right. It is a useful counterweight to the cathedral quarter: quiet galleries, clean lines, and terrace views over a part of the old city that many pilgrims miss.