Église Sainte-Radegonde de Riantec, Neo-Gothic and Neo-Byzantine church in Riantec, France

Église Sainte-Radegonde de Riantec is a Neo-Gothic and Neo-Byzantine church built of light gray stone, with a tall tiered spire topped by a small cross. Its long body has a dark sloped roof, rows of pointed windows, and a covered arcade of short pillars forming pointed arches. Inside, the Mauméjean workshop created Art Deco stained glass, mosaics, and frescoes.

The original church from the 11th century was destroyed in 1917 and later reconstructed between 1923 and 1927 by architect René Guillaume. The rebuilding effort restored the structure and allowed for the creation of the interior features visible today.

The parish's patron is Radegonde of Poitiers, wife of Clotaire I five centuries before the church's founding, an uncommon dedication in Brittany; the rector in 1902 could only suggest missionaries from Poitiers may have stopped here. On 13 August a procession went to the Sainte-Radegonde fountain, whose water was held to heal children. The cult of the Cross is also observed, as at Poitiers.

The church stands in the village of Riantec, in the Morbihan department of Brittany. The fountain of Sainte-Radegonde lies about one kilometre from the village centre, near the Riantec pond, and the procession to it was held each 13 August. The building is reached on foot from the surrounding streets.

Nearby stands a fountain dedicated to Saint Radegonde that fills with seawater during high tide and transforms to fresh water as the tide recedes. This unusual feature makes the site memorable and shows the connection between the sanctuary and the natural environment.