Introduction to St. Margaret's Chapel: St. Margaret's Chapel is located on the east front edge. It is the oldest existing building in the castle and even in the entire city of Edinburgh. The beautiful stained glass in the chapel The window depicts the holy queen of Markham III, to whom the chapel was built and dedicated by his son David I in the early 12th century.
The chapel was used as a gunpowder warehouse for more than 200 years, and later became part of the garrison church. It was not restored to its original appearance until the mid-19th century. Today this modest chapel remains a religious site, hosting weddings and christenings. Every week, an Edinburgh woman named Margaret takes turns coming here to lay flowers and clean the decorations.