Ernstbrunn castle became the seat of the Ernstbrunn branch of the Counts of Sinzendorf in 1592. After the last Sinzendorf died in 1822, it was inherited by the Köstritz branch of the ruling princely House of Reuss of whom it remains their main family seat until today.
The castle is an elongated structure with four ascending courtyards on the northern slope of the Semmelberg above Dörfles. The medieval core castle on the northern rocky spur was continuously expanded during the Late Renaissance, Baroque, and Classicism periods with new groups of buildings. The core castle, dating from the 12th and 13th centuries and surrounding the innermost courtyard, sits on a free-standing limestone rock on three sides, which drops steeply towards the village of Dörfles. It forms an elongated octagon. The wall thickness of the outer wall is up to three meters. It is further reinforced on the southeast by the square keep. Originally, this keep had only three floors but was extended by an additional floor in the 16th/17th century.
In front of the gate is an early Baroque fountain. This fountain has a total of 16 coat of arms representations, 4 at the top of the shaft below the fountain bowl and 12 in pairs around the edge of the hexagonal basin.
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.