The Sandomierz Royal Castle was built on a slope of Vistula River by Casimir III the Great and extended in the 16th century. The original building was blown up in 1656, leaving only the west wing standing. It was later transformed into a Renaissance styled residence with the west wing preserved as a museum.
The 14th-century castle was built on the site of the existing stronghold in the 10th century. Between 1146-1166 it was the seat of Prince Henry of Sandomierz, son of Bolesław III Wrymouth. The Gothic castle was built by Casimir the Great. The remnants of the Gothic structure are visible in the foundations of the octagonal tower of the south corner, which is the oldest part of the monument. The existing tower was built during the reign of Casimir IV Jagiellon in the 15th century as an integral part of the so-called Great House, the seat of the prince.
During the reign of Sigismund I the Old and Sigismund II Augustus, the castle was enlarged. The Sigismund the Old's cornerstone preserved above the entrance on the east side of the array. It bears the date 1520 and a cartouche with Sigismund's eagle. The construction was supervised by the Royal architect Benedyct Sandomierski, who erected two-storey arcaded cloisters around a closed courtyard.
During the Deluge the castle was blown up by the retreating Swedish troops of general Sincler. About fifty Poles, who entered the abandoned castle, were killed. The survived western wing of the castle was later rebuilt during the reign of king John III Sobieski between 1680-1688.
Derbent is the southernmost city in Russia, occupying the narrow gateway between the Caspian Sea and the Caucasus Mountains connecting the Eurasian steppes to the north and the Iranian Plateau to the south. Derbent claims to be the oldest city in Russia with historical documentation dating to the 8th century BCE. Due to its strategic location, over the course of history, the city changed ownership many times, particularly among the Persian, Arab, Mongol, Timurid, Shirvan and Iranian kingdoms.
Derbent has archaeological structures over 5,000 years old. As a result of this geographic peculiarity, the city developed between two walls, stretching from the mountains to the sea. These fortifications were continuously employed for a millennium and a half, longer than any other extant fortress in the world.
A traditionally and historically Iranian city, the first intensive settlement in the Derbent area dates from the 8th century BC. The site was intermittently controlled by the Persian monarchs, starting from the 6th century BC. Until the 4th century AD, it was part of Caucasian Albania which was a satrap of the Achaemenid Persian Empire. In the 5th century Derbent functioned as a border fortress and the seat of Sassanid Persians. Because of its strategic position on the northern branch of the Silk Route, the fortress was contested by the Khazars in the course of the Khazar-Arab Wars. In 654, Derbent was captured by the Arabs.
The Sassanid fortress does not exist any more, as the famous Derbent fortress as it stands today was built from the 12th century onward. Derbent became a strong military outpost and harbour of the Sassanid empire. During the 5th and 6th centuries, Derbent also became an important center for spreading the Christian faith in the Caucasus.
The site continued to be of great strategic importance until the 19th century. Today the fortifications consist of two parallel defence walls and Naryn-Kala Citadel. The walls are 3.6km long, stretching from the sea up to the mountains. They were built from stone and had 73 defence towers. 9 out of the 14 original gates remain.
In Naryn-Kala Citadel most of the old buildings, including a palace and a church, are now in ruins. It also holds baths and one of the oldest mosques in the former USSR.
In 2003, UNESCO included the old part of Derbent with traditional buildings in the World Heritage List.