The Kronverk (from the German Kronwerk — crown-shaped fortification) is a pre-fortification structure consisting of a bastion and two half-bastions forming a crown shape (hence the name). The Peter and Paul Fortress required reliable protection from the north, from the side of Berezovy (later City) Island, as shown by the events of 1705, when Swedish Lieutenant General Baron G. Y. Meidel attempted to approach the fortress under construction from the land side.
Construction of the earthworks of the Kronverk began in 1705. Researchers suggest that the project development involved the German architect W. A. Kirschenstein, the French-origin military engineer J. G. Lambert de Guerin, as well as Peter I himself. The Kronverk, framed by two ravelins, is compositionally close to similar structures by Dutch fortification engineers.
A distinctive feature of the Kronverk’s flanks were orillons — projections that shielded the flank embrasures. Such orillons were added by D. Trezzini, following the traditions of the Italian school of fortification, in 1707–1709 to the flanks of the Zotov and Golovkin bastions of the Peter and Paul Fortress. At the same time, orillons appeared on the Kronverk.
The Kronverk Canal — a water moat bordering the Kronverk territory from the north — is artificial in origin. Behind the moat was a gentle embankment called the glacis. Behind the counterscarp of the moat was a "covered way," whose outline ran parallel to the facades of the bastions and ravelins. Characteristic of Italian fortresses, the "covered way" served as a gathering place for troops preparing for sorties.
From 1723 to 1765, Peter I’s boat was stored in the Kronverk — the vessel on which the tsar in his youth mastered the basics of seamanship — the "grandfather of the Russian fleet," as well as other ships significant in Russian military history. The Kronverk housed the provisions yard, artillery and gun yards, the arsenal of the Preobrazhensky Regiment, and barracks for the garrison.
The Kronverk underwent reconstruction in 1752 (under the direction of engineer Abram Petrovich Hannibal, "Peter the Great’s Moor") and in the 1800s. The timber-earth structure was raised on a stone foundation, while its main construction remained wooden.
Until 1838, the Kronverk was part of the fortifications of the Peter and Paul Fortress. On its rampart, on July 13, 1826, five participants of the Decembrist uprising were executed. In 1975, an obelisk was erected at this site. Simultaneously, inside the Kronverk, a monumental Arsenal building was constructed according to the design of architect P. I. Tamansky, during which a significant part of the ramparts and fortifications was ... At the beginning of the 19th century, the area was assigned to the Ministry of Commerce; from 1808, a navigation and shipbuilding school operated here. In 1800, the Kronverk reconstruction was carried out by P. P. Berg.
From 1869, artillery pieces relocated from the Old Arsenal building, old Russian and trophy guns, standards, and banners were placed in the eastern part of the Kronverk; from 1872, this collection was named the Artillery Museum. Between 1849 and 1860, the glacis area was transformed into the Alexander Garden and a menagerie was established.
The building is horseshoe-shaped in plan, stylized as a medieval fortress. The walls are made of limestone slabs and faced with brick. Gothic motifs are used in the interior decoration. The building has two floors, with mezzanines above the galleries of the first floor. Since 1861, a gorge wall with gates was built on the southern side.
Currently, the remains of the fortifications are located on the territory of the Military-Historical Museum of Artillery, Engineering Troops, and Signal Corps. The Kronverk of the Peter and Paul Fortress is a federal-level fortification monument.
Sources:
https://petersmonuments.ru/russia/memorials/kronverk-petropavlovskoy-kreposti-s-peterburg/
https://ru.wikipedia.org/wiki/Кронверк_Петропавловской_крепости
