Saint Nicholas Cathedral (officially Cathédrale Notre-Dame-Immaculée) is the cathedral of the Roman Catholic Archdiocese of Monaco, where many of the Grimaldis were buried, including Grace Kelly and more recently, Rainier III.
The cathedral was built in 1875-1903 and consecrated in 1911, and is on the site of the first parish church in Monaco built in 1252 and dedicated to St. Nicholas. Of note are the retable (circa 1500) to the right of the transept, the Great Altar and the Episcopal throne in white Carrara marble.
Pontifical services take place on the major religious festivals such as the Feast of Sainte Dévote (27 January) and the National holiday (19 November). On feast days and during religious music concerts, one can hear the magnificent four-keyboard organ, inaugurated in 1976.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.