Basilica of Santo Stefano Rotondo

One of the oldest circular churches in Rome, this fifth-century basilica on the Caelian Hill is built to a rare centralised plan, its ring of ancient columns supporting a tall central drum lit from above. The unusual layout, evoking early Christian rotundas of the Holy Land, gives the interior a hushed, otherworldly quality. Around the walls runs a stark sixteenth-century fresco cycle depicting the martyrdoms of the saints in graphic detail. It stands among gardens away from the crowds, quiet and enigmatic.