Gdov was established as an outpost of the Pskov Republic. It occupied a strategically important position, being close to Lake Peipus, separating Livonia and Rus. Located on an important road to Pskov, Gdov protected it from the north. Its first mention in the chronicles dates back to 1323. Initially, the fortress was a mixture of wooden and earthen fortifications. However, the level of protection was deemed insufficient against the rising threat of the German incursion. Construction of a stone Kremlin, initially with wooden elements, commenced in 1431. The walls were constructed of alternating layers of boulders and Devonian sandstone, reaching 4 m in thickness and 8 m in height. The Kremlin had become fully stone-built by the middle of the 15th century.
The Kremlin had been attacked on numerous occasions by German, Polish, and Swedish forces. In March 1480, Gdov was attacked by forces of the Livonian Order that burned the posad and laid siege to the Kremlin, attempting to infiltrate it in a few places at the same time. Vastly outnumbered, the Gdov forces had to use every means of defence available to them, from artillery to burning tar and boiling water, successfully preventing the Order from reaching its goal.
The Ingrian War began in 1610, marking the onset of a Swedish invasion. By 1613, the Kremlin was besieged again. The Swedish forces managed to capture it, only to lose control of it later that year. In 1614, another attempt was made, with Gustavus II Adolphus, the King of Sweden personally commanding the operation. The Kremlin fell again remaining under Swedish control until 1621 when a peace treaty was signed under which Gdov was returned to Russia.
During the 17th century, the Kremlin was continuously damaged by siege. It sustained major damage to its stonework; signs of explosions have been identified. In 1657, during the course of another Russo–Swedish War, it withstood a siege laid by eight thousand soldiers led by Magnus Gabriel De la Gardie. In 1686, the Kremlin was severely damaged by fire. By the end of the century, is started to lose its strategic importance.
In 1706, Gdov was visited by Tsar Peter the Great. He ordered the walls strengthened by covering them with earth. Currently, the stone towers are also covered by earth, and have been ever since the construction of the town's park took place in the 19th century. Later in the 18th century, when the kremlin had totally fallen into disuse, parts of the walls were taken apart. In 1781, the demolition of the kremlin was temporarily halted by order of Catherine the Great.
In February 1944, the Kremlin was razed almost entirely by the retreating forces of Nazi Germans. All the structures within the Kremlin walls, including a cathedral with a 52 m tall bell tower, churches, and hundreds of merchants' houses were destroyed by explosives; only the walls remained.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.