Today Orphir contains the remains of Scotland's only surviving circular medieval church. Built in the late 11th, or early 12th century, the Orphir Round Church is thought to have been built by Earl Hakon. Dedicated to Saint Nicholas, its design was inspired by the Church of the Holy Sepulcher in Jerusalem.
At the time of the church construction, the Great Crusades were in full swing and the circular church had become a popular design with returning crusaders attempting to copy the famous structure in the Holy Land.
Originally, the church consisted of a circular nave just over six metres in diameter and an apse. The apse remains today, along with a small section of the nave's eastern section.
The church survived, almost complete, until the middle of the 18th century when sections were pulled down and the stone used to construct the new parish church. The replacement parish church did not last and no trace survives today.
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.