The design of a new structure to replace the old ruined castle of Poppelsdorf commenced in 1715 at the request of the owner, Joseph Clemens, Archbishop-Elector of Cologne, who engaged the French architect Robert de Cotte. Clemens wanted a maison de plaisance that would be near his remodeled Bonn Palace one-half mile to the north. There was to be a canal between the two, following the example of the Palace of Versailles and the Trianon de Marbre.
Work came to a halt after Clemens' death in 1723, but his nephew and heir, Archbishop of Cologne Clemens August, undertook a second campaign of construction in 1745–1746.
Under the Prussian rule, in 1818 the Palace and the nearby Park became part of the University of Bonn. In the same year the Park was converted to the Botanical Garden of Bonn, which today contains about 0.5 hectares of greenhouse area with eleven greenhouses and about 8.000 different plants.
In 1944 the Palace was heavily damaged by an Allied air attack. It has been rebuilt in a much simpler appearance from 1955 on.References:
Derbent is the southernmost city in Russia, occupying the narrow gateway between the Caspian Sea and the Caucasus Mountains connecting the Eurasian steppes to the north and the Iranian Plateau to the south. Derbent claims to be the oldest city in Russia with historical documentation dating to the 8th century BCE. Due to its strategic location, over the course of history, the city changed ownership many times, particularly among the Persian, Arab, Mongol, Timurid, Shirvan and Iranian kingdoms.
Derbent has archaeological structures over 5,000 years old. As a result of this geographic peculiarity, the city developed between two walls, stretching from the mountains to the sea. These fortifications were continuously employed for a millennium and a half, longer than any other extant fortress in the world.
A traditionally and historically Iranian city, the first intensive settlement in the Derbent area dates from the 8th century BC. The site was intermittently controlled by the Persian monarchs, starting from the 6th century BC. Until the 4th century AD, it was part of Caucasian Albania which was a satrap of the Achaemenid Persian Empire. In the 5th century Derbent functioned as a border fortress and the seat of Sassanid Persians. Because of its strategic position on the northern branch of the Silk Route, the fortress was contested by the Khazars in the course of the Khazar-Arab Wars. In 654, Derbent was captured by the Arabs.
The Sassanid fortress does not exist any more, as the famous Derbent fortress as it stands today was built from the 12th century onward. Derbent became a strong military outpost and harbour of the Sassanid empire. During the 5th and 6th centuries, Derbent also became an important center for spreading the Christian faith in the Caucasus.
The site continued to be of great strategic importance until the 19th century. Today the fortifications consist of two parallel defence walls and Naryn-Kala Citadel. The walls are 3.6km long, stretching from the sea up to the mountains. They were built from stone and had 73 defence towers. 9 out of the 14 original gates remain.
In Naryn-Kala Citadel most of the old buildings, including a palace and a church, are now in ruins. It also holds baths and one of the oldest mosques in the former USSR.
In 2003, UNESCO included the old part of Derbent with traditional buildings in the World Heritage List.