after the Russian Revolution of 1917 the prisoners, both political and criminal, were released, and set the prison on fire. Shortly before Shlisselburg was occupied by the German troops (8 September 1941), a garrison of 350 Red Army soldiers was sent to the fortress on Orekhovets island to bring supplies and munitions to the frontline. The garrison held the abandoned castle for 500 days preventing the Germans from landing there and cutting the last transit route from Leningrad to the mainland. Heavy artillery fire by the Germans destroyed all the buildings inside the fortress and part of the outer towers and walls, but despite numerous attempts the fortress was not captured. During Operation Iskra (18 January 1943) the siege of the fortress was lifted. The war completely devastated the fortress. Of the original ten towers, the fortress retains only six (five Russian and one Swedish). Renovation of the walls and towers has been slow, although it is still underway. A stone monument in memory of the first Russo-Swedish peace treaty (1323) has been placed inside the fortress. Tourists can reach the island from May to October via Shlisselburg or from the Northern bank of Neva, via Petrokrepost railway station with regular ferries that run every 10–15 minutes. Town A predecessor of the town was a posad that first appeared around the citadel on the island and in the late 15th–early 16th century shifted to both banks of the Neva. Once Muscovites rebuilt the old citadel into a powerful stronghold leaving no place for residential purposes, residents and merchants were only allowed to the island to seek shelter from advancing Swedish troops. A posad on the southern bank was more convenient for its population, unlike for those living on the northern coast, it was easier to flee the enemies to the southeast, into the Russian mainland. The southern posad of Oreshek was turned into a town in 1702 by Peter the Great. In the course of Peter's administrative reform, Shlisselburg was included in Ingermanland Governorate (known since 1710 as St. Petersburg Governorate). In 1727, it became a part of Sankt-Petersburgsky Uyezd, and in 1755 Shlisselburgsky Uyezd was established. In 1914, Sankt-Peterburgsky Uyezd was renamed Petrogradsky Uyezd. The Old Ladoga Channel that divides the town into two parts was constructed from 1719 to 1731 to ensure the safety of the vessel traffic along the southern coast of the dangerously turbulent Lake Ladoga.