In the middle of the 1630s a new fortress, the so-called Citadel, began construction in the North part of the Old City. Originally along with the castle it was included in the joint fortification system of Riga city, but at the end of the 17th century while carrying out a design of Eric Dalberg (1625 - 1703), a Swedish war engineer, the Citadel was split from the castle and moved further to the north. Thus a fortress was formed, separated from the city, with six bastions: Victoria’s (later Christina’s) bastion at Riga Castle, Carl Gustav’s, Carl’s XI, Gustav’s I, Carl’s IX and Gustav Adolph’s bastions, and with two ravelins of Prince Gustav and Prince Carl.
Considerable changes to the Citadel started at the end of the 18th century and in the beginning of the 19th century when the old wooden buildings were changed to stone buildings. A new chief commandant’s house, guardhouse, storehouses, barracks etc. were built. Many of these buildings were gradually demolished in Soviet times. An exception is the former St. Peter and Pavil Orthodox Church, designed by an architect Christoph Haberland. The chapel was built in 1781 – 1785. In its composition a common method of Russian architecture of that time was used: a tower with several layers was attached to the parish room in gammadion form in the west part. In the building’s exterior decoration Haberland introduced forms and motives borrowed from antique heritage.
Up to nowadays two Citadel’s victual storehouses (1723 and 1728), guardhouse (1775) and barracks (end of the 18th century) have been preserved.