The church of Saint-Pierre d'Andenelle with its tower dates from the 12th century. Built of reddish sandstone, this remarkable monument of Mosan architecture is one of the oldest in the region. It underwent alterations in the 17th century (the inside pillars were changed), in 1853 (the entrance portal, which used to be found in the north, was moved to the west), in 1860 (building of the transept), in 1875 (the portal was moved to the north as a result of the building of the Andenne-Haillot road) and in 1923 (building of the side aisles). It is a mistake to believe that it was built in a hollow. In times past, it was level with the road and the square. People entered on a level, through a big door at the foot of the tower, next to the stream. But when the Haillot bottom road was built, the portion of the road was raised and people had to go down a few steps to enter the church.
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.