Perched on a commanding rise in the southern part of the village, Oldofredi Castle was one of three fortifications built to defend Monte Isola. The complex is composed of several interconnected buildings arranged around a courtyard that opens toward the south. The main entrance lies beside the Church of San Michele, with which the castle shares a boundary, though the courtyard can also be reached via a stone staircase climbing up from the southern lakeshore. The castle’s origins almost certainly date back to the medieval period. Over the centuries, it was extensively remodeled—both inside and out—to transform it into an elegant noble residence. Notable additions include the north‑eastern entrance portico with its pointed arches and the dovecote above; along the eastern wing, a charming loggia supported by columns and pilasters in Sarnico stone; and along the western side, a portico of seven arches surmounted by a loggia of fourteen arches. The latter originally featured Sarnico stone details, later replaced with masonry pillars in more recent times. The oldest section is the lakeside range, while the uphill portion is more recent, built in exposed masonry and largely reconstructed. On the southern side of the medieval core once stood a tower—described by Giovanni da Lezze in 1610—demolished around 1870. On an exterior ground‑floor wall survives a remarkable late‑Gothic fresco of Lombard workmanship, dated 1458, depicting the Madonna enthroned with the Christ Child, seated on a dramatically foreshortened throne.