Villa Magni, Italian national heritage villa in San Terenzo, Italy.

Villa Magni is a three-storey building at the eastern edge of San Terenzo, where the land rises toward the Marigola promontory. Its seaward facade has a five-arch portico, the central arch wider and taller, with five doors on the first floor and five small windows above. A rear wing gives the house an L-shaped plan.

The building was first constructed during the 16th century as a monastery for a religious order. It later became a private residence occupied by a notable literary family during 1822.

Locals call it Casa Magni or Villa Shelley. In 1822 the Shelleys scandalised San Terenzo: they lived without furniture, slept on straw mattresses lent by villagers, ate only bread, tea and fruit, and bathed nude in the bay. Mary recalled Shelley walking naked from the sea past guests taking tea at the door.

The building has limited public access but the exterior can be viewed from the surrounding coastal paths at any time of year. Walking along the nearby waterfront gives you different perspectives of how the structure sits in its location.

Edward Trelawny described the ground floor as having no floor, used to store boats and gear, with a single upper storey of a central hall and four rooms. A photograph from around 1880 shows an awning over the portico balcony, forming a veranda.