On the South Bank of the Pregel river in Kaliningrad Gate is located Fredricksburgh fortress, built in 1852 by court architect William IV - August Stylemom. Gate is the only surviving part of the castle Friedrichsburg.

Friedrichsburg fortress built in 1657 by the project P. H. Ottera for the protection of königsberg from the river, had the shape of a square and corner bastions with euphonious names: ruby, Pearl, Diamond and Emerald. In the courtyard of the fortress housed the barracks, Church, office, barns, prison and Zeughaus. Friedrichsburg remarkable visit in 1697, the Russian Tsar Peter the great under the name of constable Peter Mikhailovich for the development of artillery science. On his return to Moscow on the orders of Peter was built several FORTS (Alexander-the trench, the Citadel and Groslot) on Kotlin island, a specimen of which was Friedrichsburg castle.

In the mid-nineteenth century with the construction of new rampart fortifications around Koenigsberg (now Kaliningrad), the Friedrichsburg was modernized in the eponymous Fort. In this time period were built of brick gate, extant. In 1910, the Fort was declared obsolete and sold to the city authorities. During the construction of the Imperial Railways the main part of the former fortress was demolished, backfilled ditches, shafts razed, and on the territory of the Fort were laid railway. From the structure leaving only the barracks at the walls of the South-East Bastion and gate. During the storming of Koenigsberg (April 1945.was lost the last tower, South wall of the courtyard and heavily damaged gate. In the 1960s, the ruins Friedrichsburg gates were declared a monument of architecture, and since 2002 are the object of cultural heritage of Federal value). In March 2007, a unique historical object was donated to the Museum of the World ocean.

In our days the restored Gate Fredricksburgh fortress represent a massive brick building with coat of arms on the façade, towers, iron gates and cobblestone antique patio. On-site historic buildings: restoration laboratory, Museum shipyard and Lodeynoye yard and at the gate there are three old cannons. Within the gate is a Museum of marine glory of Russia, the exhibition which tells the history of the airline fleet includes unique exhibits and a replica of the stern of the battleship "Poltava", the pride of Peter fleet. At the gate Fredricksburgh fortress near the window stands a bronze Kenigsbergskii cat, which is a prototype of Hoffmann Kota philosopher Murr.