Mon Repos or 'Monrepos' is a manor house and landscaped English park in Vyborg. Between 1788, when Ludwig Heinrich von Nicolai bought it, and 1943, 'Monrepos' was owned by the family of Baron Nicolai (better Nicolay). The historic core of the museum complex is a manor from the early 19th century. This consists of the Main house and the Library house, monuments of wooden classical architecture, and the landscape rock park designed in the romantic style, and which remains a unique monument of gardening art. Among the park designers were such architects as J. Martinelli, Auguste de Montferrand, A. Shtakenshneider, Ch. Tetam, artists Ya. Mattenleiter, and P. Gonzago. The area of the park is marked by special physical and geographical features, like the old Wiborgite granite, which is named after Vyborg, and glacial formations of up to 20 metres high. In this nature reserve, 50 species of different plants can be found, some of them being rare. Its fauna is diverse as well: the park abounds in numerous birds and animals.
References:The Petersberg Citadel is one of the largest extant early-modern citadels in Europe and covers the whole north-western part of the Erfurt city centre. It was built after 1665 on Petersberg hill and was in military use until 1963. It dates from a time when Erfurt was ruled by the Electors of Mainz and is a unique example of the European style of fortress construction. Beneath the citadel is an underground maze of passageways that can be visited on guided tours organised by Erfurt Tourist Office.
The citadel was originally built on the site of a medieval Benedictine Monastery and the earliest parts of the complex date from the 12th century. Erfurt has also been ruled by Sweden, Prussia, Napoleon, the German Empire, the Nazis, and post-World War II Soviet occupying forces, and it was part of the German Democratic Republic (East Germany). All of these regimes used Petersberg Citadel and had an influence on its development. The baroque fortress was in military use until 1963. Since German reunification in 1990, the citadel has undergone significant restoration and it is now open to the public as a historic site.