The Carlo al Corso church replaced an earlier church. This church likely designed by Rosario Gagliardi, was part of the town reconstruction after the 1693 Sicily earthquake.
The concave façade has three superimposed orders of columns, identified by their capitals from base to roofline as Doric, Ionic and Corinthian; in the progression expected in classical construction. The third story has floral oculus. The interior has a longitudinal layout with a barrel vault sustained by pilasters. The main altar was rescued from the prior church.
Inside the church, the 18th-century altarpieces display a Sacrifice of Isaac; a Flight into Egypt; a Deposition; San Carlo Borromeo ministering to those ill with the plague; a Virgin and Child with saints; Biblical Scene; St Ignatius of Loyola, founder of the Jesuit order; and wood icon of St Aloyitius Gonzaga, another Jesuit saint. The main altar is flanked by marble statues symbolizing Faith and Hope respectively, sculpted by Giuseppe Giuliano. The nave ceiling is frescoed by Costantino Carasi, depicting the Transfiguration and the Healing of the Paralytic, with a central panel depicting the Triumph of the Agnus Dei. The spandrels that support the dome are frescoed with the evangelists, and just below are four allegorical statues depicting the respective cardinal virtues.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.