The Württemberg Mausoleum is a memorial standing on the peak of Württemberg Hill at the westernmost end of Schurwald woods overlooking the Neckar river. The memorial was built for Catherine Pavlovna of Russia (1788–1819), the second wife of William I of Württemberg (1781–1864). The remains of William I and his daughter Maria Friederike Charlotte of Württemberg (1816–1887) are also housed in the mausoleum.
The mausoleum was built after the death of Queen Catherine between 1820 and 1824 based on a design drafted by Giovanni Salucci. The location on the former site of Wirtemberg castle was chosen as the home of the House of Württemberg.
Between 1825 and 1899 the mausoleum was used as a Russian Orthodox Church place of worship. The memorial is still used to this day for a Russian Orthodox service every Pentecost.
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.