St. Panteleimon Monastery is built on the southwest side of the peninsula of Mount Athos. It is often referred to as 'Russian' and does have historical and liturgical ties to the Russian Orthodox Church; nevertheless, like all the other monastic settlements on Mount Athos, the monastery is under the direct ecclesiastical jurisdiction of the Ecumenical Patriarchate of Constantinople and all its monks are citizens of Greece, usually naturalized.
The monastery was founded by several monks from Kievan Rus in the 11th century, which is why it is known as 'Rossikon'. It has been inhabited by mainly Russian monks in certain periods of its history. It was recognized as a separate monastery in 1169.
The monastery prospered in the 16th and 17th centuries being lavishly sponsored by the tsars of Moscovy, but it declined dramatically in the 18th century to the point where there were only two Russian and two Bulgarian monks left by 1730.
The construction of the present monastery on a new site, closer to the seashore, was carried out during the first two decades of the 19th century, with the financial help of the ruler of Moldo-Wallachia, Skarlatos Kallimachos. The monastery occupies the nineteenth rank in the hierarchical order of the twenty Athonite monasteries.
In 1913, the monastery was the site of a raging theological argument (Imiaslavie) among Russian monks, which led to tsarist Russian intervention and the deportation of approximately 800 of the monks on the losing side of the debate.
The Monastery of St Panteleimon was repeatedly gutted by fires, most famously in 1307 (when Catalan mercenaries set it aflame) and in 1968.
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.