Herford Abbey was the oldest women's religious house in the Duchy of Saxony. It was founded as a house of secular canonesses in 789, but moved later to the present site. The city of Herford grew up on this site around the abbey. The abbey was dedicated in 832 and was elevated to the status of a Reichsabtei ('Imperial abbey') under Emperor Louis the Pious (d. 840).
Between 919 and 924 Herford was destroyed by Hungarians but was rebuilt by 927. In 1147 the abbey, which by this time had almost 850 estates and farms, was granted Imperial immediacy. This made it an independent territory within the Holy Roman Empire which lasted until 1803.
In 1533, during the Reformation, Herford Abbey became Lutheran, under the Electors of Brandenburg. From 1649 for over a century the abbesses were all Calvinist but that did not alter the Lutheran character of the principality.
In 1802 the abbey was dissolved in the course of secularisation. In 1804 it was turned into a collegiate foundation for men, and in 1810 finally suppressed. The former abbey church remains in use as Herford Minster (Herforder Münster). The church is a late Romanesque hall church, built about 1220-1250. It is one of the earliest hall churches in Germany.
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.