The Orangery Palace (Orangerieschloss) was built by the Romantic on the Throne, Friedrich Wilhelm IV from 1851 to 1864. The architects Friedrich August Stüler and Ludwig Ferdinand Hesse designed it in the style of the Italian Renaissance, after the image of the Villa Medici in Rome and the Uffizi in Florence.
The middle building with its twin towers is the actual castle. This building is joined to the 103 meter long and 16 meter wide Plant Hall, with its almost ceiling-to-floor windows on the south side. In the western hall, the original floor duct heating system is still present and functioning. In the alcoves along the garden side of the castle annex, there are allegorical figures of the months and seasons. In the corner building at the end of the Orangery Hall were the royal apartments and the servants' quarters.
In front of the peristyle Elizabeth, Friedrich Wilhelm IV's wife, had a statue of the king erected in Memoriam after his death in 1861.
Behind the portico, in the middle building, lies the over two-story-tall Raffael Hall. It was based on the Sala Regia in the Vatican. Over a large skylight in the high clouded ceiling, light falls into the Museum Hall. On the red silk covered walls, hang over fifty copies of Renaissance paintings. Friedrich Wilhelm IV inherited the images from his father, Friedrich Wilhelm III, and brought them here together.
The royal apartments were outfitted in the second Rococo style, connected to both sides of the Raffael Hall. They were intended as guest rooms for Tsar Nicholas I and his wife, Alexandra Feodorovna. The Tsarina was the favorite sister of Friedrich Wilhelm IV, Charlotte, who gave up her name along with her homeland when she married.
The gardens were styled after those of the Italian Renaissance by the garden architect, Peter Joseph Lenné. In the west, below the annex, he designed the Paradise Garden in 1843/1844. In it are many exotic flowers and foliage plants. The atrium, a small building in middle of the compound, designed in the ancient style, was built on plans by Ludwig Persius in 1845. The current Botanical Garden, with its systematically arranged planting, is used by the University of Potsdam as a teaching garden.
The Norse and Sicilian Gardens lie to the east. These completely different garden sections were laid out by Lenné between 1857 and 1860. The dark, effective Norse Garden, with its pines, was to have been an element of the planned triumph street. The Sicilian Garden, with its palm tubs, myrtles, laurels, flowers, arcades, and fountains, runs jovially southward.References:
Kristiansten Fortress was built to protect the city against attack from the east. Construction was finished in 1685. General Johan Caspar von Cicignon, who was chief inspector of kuks fortifications, was responsible for the new town plan of Trondheim after the great fire of 18 April 1681. He also made the plans for the construction of Kristiansten Fortress.
The fortress was built during the period from 1682 to 1684 and strengthened to a complete defence fortification in 1691 by building an advanced post Kristiandsands bastion in the east and in 1695 with the now vanished Møllenberg skanse by the river Nidelven. These fortifications were encircled by a continuous palisade and thereby connected to the fortified city. In 1750 the fortress was modernized with new bastions and casemates to protect against mortar artillery.