Initially financed by Cardinal Alfonso Gesualdo for the Order of Theatines, the church of Sant' Andrea della Valle was begun in 1591. The architects were Giacomo della Porta, Pier Paolo Olivieri, and Carlo Maderno, who designed the spectacular dome, the highest in Rome after St Peter's.
Dome
The lantern is thought to have been designed by Francesco Borromini (1599-1667). The eight windows are separated by pairs of ionic columns. Each pair has a human face where the capitals meet.
Lantern
The facade was added in 1665 by Carlo Rainaldi. It is crowned with the pope's coat of arms and emblazoned with the inscription: ALEXANDER · SEPT · P · M · S · ANDREAE · APOSTOLO · AN · SALVTIS · MDCLXV (Alexander the Seventh, Pontifex Maximus, to St Andrew the Apostle, the year of salvation, 1665).
Entrance
The four statues on the facade depict St Cajetan, St Andrew, St Sebastian and St Andrew Avellino. Domenico Guidi carved St Cajetan and St Andrew, while Ercole Ferrata carved St Sebastian and St Andrew Avellino.
Allegorical Statues of Hope and Strength
Each statue is surmounted by a pair of putti bearing symbols of martyrdom. The allegorical statues of Hope and Strength, above the main entrance, are the work of Antonio Fancelli. The coat of arms belonged to Cardinal Francesco Peretti.
Interior
The interior has a high barrel vault and a spacious apse.
Nave Vault
The four paintings in the vault of the nave celebrate the doctrine of the Immaculate Conception. The panels depict The Expulsion of Adam and Eve from Paradise and The Vision of Our Lady to Sister Orsola Benincasa by Virginio Monti, andThe Proclamation of the Dogma of the Immaculate Conception and The Visitation by Salvatore Nobili (1865-1919). The picture of The Expulsion of Adam and Eve is unusual in that it depicts Mary Immaculate remaining in Paradise.
The panels by the windows depict the Apostles and the Evangelists and are by Silvio Galimberti.
Funerary Monument to Pope Pius II
High up on the walls before the crossing are two funerary monuments, one to Pope Pius II (r. 1458-64), and the other to his nephew Pope Pius III, who only reigned for twenty-six days (r. 22.09.1503 - 18.10.1503).
Both tombs were originally in St Peter's Basilica and were brought here in 1614. The four-storey monument of Pius II (c. 1470) is attributed to Paolo Taccone (also known as Paolo Romano). The two reliefs show Pope Pius II receiving the head of St Andrew the Apostle at Sant'Andrea a Ponte Milvio outside Rome; and Pope Pius II being introduced to the Virgin Mary. The former event the pope himself considered to be the most important of his pontificate.
Funerary Monument to Pope Pius III
The funerary monument of Pope Pius III was clearly modelled on the tomb of his uncle Pope Pius II. It was sculpted by Sebastiano Ferrucci in 1503.
Interior of Dome
The fresco in the dome is the Glory of Paradise (1621-27) by Giovanni Lanfranco (1582-1647). His contemporary Domenico Zampieri (1581-1641), better known as il Domenichino (on account of his diminutive stature) added the frescoes in the pendentives and the scenes from the life of St Andrew in the vault of the apse.
Apse
The three large paintings above and to either side of the high altar are the work of Mattia Preti (1613-99). They depict St Andrew being raised on the cross, his crucifixion and his burial.
Vault of the Apse
The frescoes in the vault of the apse are by Domenichino. In the centre is The Call of Peter and Andrew. To the left is The Flagellation of St Andrew, while to the right is St Andrew Being Shown his Cross. The fresco in the bay vault depicts St John the Baptist Proclaiming Jesus as the Lamb of God.
Chapel of St Cajetan
The richly decorated chapel in the left transept is dedicated to St Cajetan (1480-1547), co-founder of the Theatines. The altarpiece, depicting the Virgin and Child with St Cajetan, was painted in 1770 by Mattia de Mare, but the altar dates from 1912 and was designed by the Roman architect Cesare Bazzani (1873-1939). The two statues are by the Roman sculptor Giulio Tadolini (1849-1918) and represent Abundance and Wisdom.
Funerary Monument to Gaspare Thiene
The fine funerary monument of Count Gaspare Thiene is the work of Domenico Guidi (1625-1701).
Cappella Ginnetti (aka Cappella Lancellotti)
The side chapels in the nave are identical rectangular spaces, each capped with a small dome.
The first chapel on the right, the Cappella Lancellotti, was designed by Carlo Fontana in 1670. It originally belonged to the Ginetti family, and is sometimes called the Cappella Ginetti. The altarpiece, a bas-relief in white marble, depicts The Angel Urges the Holy Family to Flee to Egypt (1675) and is the work of Antonio Raggi.
The first chapel on the left is the Cappella Barberini, which was commissioned by Cardinal Maffeo Barberini, who later became Pope Urban VIII (r. 1623-44). On October 8th 1629, Urban VIII canonised St Cajetan.
The chapel is home to a statue of St John the Baptist (1616) by Pietro Bernini, father of the great Gianlorenzo Bernini.
The Cappella Barberini is thought to have been the inspiration for the Cappella Attavanti in Puccini's opera Tosca, which is set in Rome.