Kamieniec Podolski, known as the "key to Podolia", had heavy, but obsolete fortifications, and a garrison of about 1500 soldiers (Poles, Ukrainians and Lithuanians). The Ottoman army was under command of Köprülü Fazıl Ahmed Pasha and numbered 150 thousand soldiers with reinforcements from the army of Tatars, Moldavians, Wallachians and Cossacks. Polish forces were commanded by Starosta of Podole, Mikolaj Potocki, and consisted of several units, such as infantry regiment of Bishop of Krakow Andrzej Trzebicki, two regiments of Captains Wasowicz and Bukar, permanent garrison of Major Kwasiborski, and other smaller units under Jan Mokrzycki, Jerzy Wolodyjowski, Rotmeister Myliszewski, Chorazy Wojciech Humecki, Stolnik Stanislaw Makowiecki, and Czesnik Jozef Wasilkowski. Polish forces of some 1,500 were inadequate to successfully defend such a large fortress.
First Crimean Tatar units appeared near Kamieniec Podolski on August 12, and two days later, main Ottoman army camped by the town. After building seven large sconces, Turkish artillery began a barrage with its 120 modern cannons. It paralyzed Polish defence, and on August 20, the Turks managed to score a direct hit in one of the towers of the Old Castle, which served as an ammunition depot. The tower blew up in a large explosion, which was followed by a Turkish attack on Kamieniec. Poles managed to defend the fortress, but with very heavy losses. After the attack, Mikolaj Potocki decided to abandon the New Castle, under which Turkish miners dug deep tunnels, placing explosives in them. The Old Castle with its medieval walls was not prepared for a modern siege, and Potocki’s decision placed the defenders in a very difficult position. On August 25 the Turks dug a tunnel under one of the towers, and managed to destroy it. Another attack followed, again repelled by the Poles.
On August 26, Potocki decided to capitulate. Polish forces left Kamieniec on August 30, and three days later, the Pasha entered the city. Turkish occupiers remained in Kamieniec for the next 27 years, until 1699. In 1692, HetmanStanislaw Jan Jablonowski built the stronghold of Okopy Swietej Trojcy, located some 20 kilometres (12 mi) from Kamieniec. Its purpose was to stop a possible Turkish attack.
The loss of the key fortress obliged Poland to sign the Peace of Buczacz, which compelled Poland and Lithuania to pay a yearly tribute to the Turks of 22,000 ducats. Kamieniec returned to Poland in 1699, following the Treaty of Karlowitz.