This is a modest monastery of Benedictine nuns located in the area known as Ribeira Sacra. There are very few references to this house; it is mentioned for the first time in 1108, when Visclavara, its abbess, acted as a witness in a donation made in favor of San Salvador de Ferreira. The monastery is mentioned again in 1280.
In 1494, during the reforms of Benedictine houses, San Fiz was without an abbess, which facilitated its suppression and the incorporation of its assets into the monastery of San Paio de Antealtares. Its church, now serving as a parish church, has been preserved and dates back to the Romanesque period. It features a single nave, almost square, which connects with the transept covered by 16th-century vaults, where three apses originally opened. The central apse is semicircular; the southern one is rectangular, while the northern one was replaced in the 16th century by a chapel. The church preserves Baroque altarpieces and several tombs, among which the ones belonging to Gómez Ares Mosqueira and his wife, Guiomar Méndez de Ambía (15th-16th centuries), stand out.
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