Chiesa di San Michele is one of Cagliari's most exuberant Baroque interiors, hidden in the Stampace quarter behind a relatively restrained facade. Inside, the Jesuit taste for theatre takes over: coloured marble, gilded altars, sculptural detail, and a nave designed to pull the eye forward.
It makes a good contrast with the more fortress-like mood of Castello. Visit while wandering Stampace's lanes, especially if you enjoy churches that feel urban and intimate rather than cathedral-sized. The decoration is dense, but the space is small enough to take in without fatigue.