The area of Piano was inhabited from prehistory, colonised by the Greeks, and inhabited by the Osci and Campanians.

In roman times it was called Planities, due to the flat land. The popular names are two: “Caruotto” and “Cassano”, which, according to some, refers to the effects of an ancient earthquake of the 16th century, which had damaged part of the city (cà rotto) and preserved the other (cà sano). It corresponds to Marina di Cassano, the village of the anglers, which is suggestive for its position, defined by the tufa cliff crossed by a connection road with its characteristic hairpin turns. The old town extends around the Parish of Saint Michael the Archangel, of the 9th-10th century. Several times destroyed and rebuilt, elevated to a pontifical basilica in 1914: with a Latin cross plan and the wide central nave is surmounted with a choir with an organ and two founts of the 18th century. On the coffered ceiling, there are the paintings of Solimena and Paolo De Matteis dedicated to the Stories of the life of Saint Michael. The balustrade which delimits the presbytery is made with marble and is a work of Giambattista Antoni, with four angels of Bernini style. In the sacristy, there are three important paintings: the Scenes of the plague of Giuseppe Castellano; the Madonna della Neve (Our Lady of Snow) from the school of the venetian painter Giovanni Bellini also known as Giambellino (of the 15th century) and Saint Thomas touching the side of Jesus of Pacecco De Rosa. Next to the Basilica, there is the Convent of the Augustinian with the annexed Chiesa della Misericordia (Church of Mercy), completed in 1739. At the end of the stairs starting from Corso Italia, there is the Carmelite Convent with the Church of the saints Joseph and Theresa, with three naves, built between 1663 and 1687. You can also admire the large painting of Solimena style artist : Romulado Formosa, who represents  Saint John of the Cross. The Church of Madonna delle Grazie or of Rosella, then, is linked to a miraculous event: a commoner named Rosella asked and obtained the recovery of her son, who was seriously ill, praying in front of an old painting of the Virgin Mary. She asked to a painter to clean the painting, which became resplendent, launching the popular veneration. The Church of Santissima Trinità of 1543 is also interesting, with its bell tower with a clock. Beautiful and luxurious houses recall the splendours of the past. From the monumental Palazzo Maresca in Villa Lauro, defined by Roberto Pane as the “most notable neoclassical factory of the whole region” in Villa Fondi De Sangro, built by prince of Fondi don Giovanni Andrea De Sangro, with his wide park overlooking the sea. The territorial archaeological museum of the Sorrentine Peninsula is hosted in the villa. The museum is dedicated to the archaeologist “Georges Vallet”, which presents the result of the excavation campaigns continuing in the Sorrentine Peninsula, with testimonies of settlements from Prehistory to roman times, in a wider context of the ancient Campania.