Rosslyn Chapel was founded on a small hill above Roslin Glen in the mid-15th century. The chapel was founded by William Sinclair, 1st Earl of Caithness of the Scoto-Norman Sinclair family.
After the Scottish Reformation (1560), Roman Catholic worship in the chapel was brought to an end, although the Sinclair family continued to be Roman Catholics until the early 18th century. From that time the chapel was closed to public worship until 1861, when it was opened again as a place of worship according to the rites of the Scottish Episcopal Church, a member church of the Anglican Communion.
Since the late 1980s, the chapel has also featured in speculative theories concerning a connection of Freemasonry, the Knights Templar and the Holy Grail. It was prominently featured in the 2003 bestselling novel The Da Vinci Code and its 2006 film adaptation. Numerous books were published after 2003 to cater to the popular interest in supposed connections generated by Brown's novel. The chapel, built 150 years after the dissolution of the Knights Templar, supposedly has many Templar symbols.
Rosslyn Chapel remains privately owned. The current owner is Peter St Clair-Erskine, 7th Earl of Rosslyn.
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.