St. Panteleimon Monastery is a Russian Orthodox Monastery and the largest one on the peninsula. The monastery was founded by several monks from Kiev Rus in the 11th century, which is why it is known as 'Rossikon', and traditionally it was inhabited by Kiev and later by Russian Orthodox monks. 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 that 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 nineteenth century, with the financial help of the ruler of Moldo-Wallachia, Skarlatos Kallimachos. Russian monks numbered 1,000 in 1895, 1,446 in 1903, and more than 2,000 by 1913. During the Tatar yoke in Russia, most of the monks were Greeks and Serbs. Today only 35 monks live in the monastery, which occupies the nineteenth rank in the hierarchical order of the twenty Athonite monasteries. It is coenobitic. It also contains four sketes. The Monastery of St Panteleimon was repeatedly gutted by fires, most famously in 1307 (when Catalan pirates set it on fire) and in 1968.

Today, the monastery features the architecture of a small town, with buildings of various heights and many domes.  The monastery's katholikon was built between 1812–1821 and is dedicated to St. Panteleimon. It features the same style found in all the Athonite churches. Aside from the katholikon, the monastery has many smaller chapels.

Treasures held within the monastery

The library contains 1,320 Greek manuscripts and another 600 Slavonic ones, as well as 25,000 printed books. In addition it has a few priceless relics, such as the head of Saint Panteleimon, a part of a True Cross, the head of Martyr Paraskeva, the relics of  the Apostles Luke, Peter, Andrew, Matthew, Thomas as well as the relics of Maria Magdalene, Grigorios Palama, St. Anastasia, St. Ioann (Russian).

Miracle-working icons within the monastery

Our Lady of Jerusalem- the miracle-working icon is located right above the Tsar’s Gate in the Pokrov Cathedral.

The icon of the Martyr Panteleimon – is an ancient mosaic icon earlier located in the Thessalonica monastery (current Paliomonastirio).  Nowadays the icon is located in the Pokrov Cathedral. St. Panteleimon is depicted in his full height holding medical instruments in his hand.