The Albrechtsburg is a Late Gothic castle that dominates the town centre of Meissen. It stands on a hill above the river Elbe, adjacent to the Meissen Cathedral.
By 929 King Henry I of Germany had finally subdued the Slavic Glomacze tribe and built a fortress within their settlement area, situated on a rock high above the Elbe river. This castle, called Misnia after a nearby creek, became the nucleus of the town and from 965 the residence of the Margraves of Meissen, who in 1423 acquired the Electorate of Saxony.
From 1464 Elector Ernest of Saxony ruled jointly with his younger brother Albert the Bold and both had the present-day castle erected from 1471 on. The masterpiece of court builder Arnold of Westphalia, it was constructed solely as a residence, not as a military fortress, the first German castle built for such a purpose. When the brothers divided the Wettin lands by the 1485 Treaty of Leipzig, the castle of Meissen fell to Albert. Though Albert's son Duke George the Bearded resided at the Albrechtsburg, it was soon superseded by Dresden Castle as the new seat of the Wettin Albertinian line.
In 1710 King Augustus II the Strong established the Königlich-Polnische und Kurfürstlich-Sächsische Porzellan-Manufaktur, which was the first European hard-paste porcelain manufacture, at the castle under the supervision of Johann Friedrich Böttger. Meissen porcelain was produced at the Albrechtsburg until manufacturing moved to its present location in 1863.
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.