Sant'Andrea is a Romanesque church in Piazza della Repubblica, the civic heart of Orvieto, notable for its unusual twelve-sided bell tower — one of the few dodecagonal towers in Italy. The church dates from the 7th century in its origins, though the current building is mostly 13th century. Inside, the floor is a patchwork of ancient mosaic fragments.
Piazza della Repubblica, just behind the church, has the Palazzo Comunale and is a pleasant square for a pause. The combination of the old civic buildings, the old well in the square, and Sant'Andrea's distinctive tower make it one of the most characterful spots in Orvieto after the Duomo piazza.