1. Rouen to Perriers-sur-Andelle

Saint Ouen, Dadon his birth name, was bishop of Rouen from 639 to 689 and was blessed by Saint Colomban during his visit to Ussy-sur-Marne at the home of his father Authaire in 610. He became a faithful disciple of Luxovien monasticism practising the rule of the good Fathers Benoit and Colomban, a formula mentioned in the foundation charters that have come down to us. It was under his episcopate that Luxovien monasteries were established in the Seine valley. Bishop Ouen will be present on the foundation charters of the abbey of Fontenelle (Saint Wandrille), Jumièges (Saint Philibert), La Trinité à Fécamp, the abbey of Montivilliers, the abbey of Pavilly.
Saint-Ouen Abbey was founded after the death of Saint Ouen around 750. The church replaced a chapel housing the tomb of Saint-Ouen.
The abbey of Saint-Ouen was one of the most powerful Benedictine monasteries in Normandy. After the Revolution, the municipality moved into the former monks' dormitory, a beautiful classical building from the mid-18th century. The abbey church, which many visitors take for the cathedral because of its majestic proportions, stands in the former gardens of the convent. Saint-Ouen is thus one of the rare examples of the radiant Gothic. Its proportions are imposing: 137m long under 33m of vaults. The interior will amaze you with its slender architecture and its exceptional luminosity. A series of 80 original stained glass windows still decorate the three levels of the church. The great organ, the last of the great instruments made by Cavaillé-Coll, another title of glory of Saint Ouen, is one of the most recorded instruments in the world.
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The church of St-Hilaire was located outside Rouen, in the Robec valley. The parish covered a suburb of rather poor weavers. The origins of the small medieval chapel are not known.  
Destroyed several times, it was rebuilt several times and enlarged over the centuries.
It was closed in 1793 and was restored in 1802,  
When it became a parish church, it was later found to be too small and unsightly. A new church replaced the old construction. Its foundation stone was laid on April 17, 1875.
It was built in a Gothic style described as "transitional". Its style borrows from Romanesque and Gothic. The building was consecrated on 14 January 1878.
The choir has two bays and a three-sided apse. It is framed by two wings terminated by apsidal chapels. One is dedicated to the Virgin Mary, the other to Saint Joseph.
The very wide transept is illuminated by two roses. To the north is the sacristy and to the south, a colonnade. The nave is 16 m wide and 17 m high. It has four bays. The last bay is surmounted by the organ loft.
The bell tower is at the crossing of the transept. It carries a stone pyramid dampened by four bells.
The church has a remarkable wrought iron choir grille with ornaments made by the Rouen ironmonger Ferdinand Marrou towards the end of the 19th century. The choir is decorated with a fresco depicting the Council of Seleucia of 359, where Saint-Hilaire was represented.
The fresco of the lantern is illustrated with the patron saints of the church of Rouen.
The stained glass windows are by Boulanger. They are illustrated with the main features of the story of Saint Hilaire.

The parish dedicated to Saint Etienne, together with the Perriers estate, was given to the Abbey of Saint-Ouen de Rouen in 1050 by William, Count d'Arques, and his brother Archbishop Mauger. The present building is a vast cruciform flint construction of Romanesque origin. At the end of the 11th century, the plan of the building, the transept, the bell tower on the crossing of the transept and the walls of the nave belong to the building. The buttresses of the nave were added in the 13th century. The western façade was rebuilt after 1868 by the architect Simon, in the style of the 13th century, as were the bays of the nave. In the 14th century, the crossing was vaulted with ribbed vaults and the choir had a flat chevet. Inside, the nave is roofed with a roofing framework with exposed crosspieces and punches, moulded sandpits and painted decoration from the end of the 16th century. In the choir is an 18th century painted and gilded altarpiece and a large 19th century glass roof by Duhamel Marette.
In Perriers-sur-Andelle, thistle was grown for the cloth factories of Louviers and Elbeuf. In 1840, three cotton mills, four wheat mills and a fuller's mill were built on the river as well as brick and plaster factories.