The Longos Vales's Monastery foundation is attributed to D. Afonso Henriques in the second half of the 12th century.
The only enduring element of the primitive medieval construction with its clearly Romanesque style is the main chapel, the remainder of the group was subjected to remodelling work when it passed into the hands of the Society of Jesus.
Nowadays, the monastery is private property, with the exception of the church which continues to be part of the parochial headquarters of the parish.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.