ORSERA. – An Istrian commune near Parenzo. Ursaria appears in the *Tabula Peutingeriana*, where the name is given to an island, corresponding in position to O.
A center of agricultural and commercial activity in the Roman age (it has an excellent natural harbor), it provides an uncommon example of a *domus ecclesiae*, discovered in 1935 near the sea. Among its various rooms, noteworthy is the Basilica (m. 9.30 x 15.20), a rectangular structure built in the mid-4th century with two annexed liturgical rooms, equipped with an apse and a narthex in the mid-5th century, and a small hall, identifiable as the catechumenate, contemporary with the Basilica. Part of the mosaic pavement is preserved, composed of 91 *eliphae* of two sizes, connected by braided bands and adorned with various symbols, including the seasons. The floor museum of the catechumenate is quadrilateral with curved sides and contains a fish pond. There are absolutely no inscriptions. In the museums, one may note the elegance of the geometric motifs, the impressionistic rapidity of the figures, the vivid sense of color, and some connections with African pavements.
Near this early Christian site is the church of S. Maria a Marina, a three-aisled structure (12th century), to which a Franciscan convent was later attached; in the village there was a Romanesque church, the ancient parish church, destroyed in 1941.
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