A huge impetus to city development was given by Queen Bona Sforza, the wife of the Polish King Sigismund the Old. She and her son, the future King Sigismund Augustus, arrived in Podillya and founded the new city of Bar, which is named after her native town Bari in Italy, on the opposite side of the Riv river. At the same time, a dam was built and a large pond was formed, which washed the ground in a semicircle, where the Queen ordered to build a wooden castle and establish a city under the protection of the walls. Bona Sforza almost immediately granted the bar Magdeburg rights, exempted its inhabitants from taxes for twenty years, and formed the Bar starostvo. All this contributed to rapid development, so soon Bar and its castle were considered the second most powerful after Kamianets.
The wooden fortress was built in 1538 and named by Polish Queen Bona. In 1636, the crown Hetman S. Koniecpolski chose Bar as his residence and began the construction of a stone castle. The author of the project was the famous French engineer de Beauplan. The fortress was square in the plan and had four bastions that reached almost 6 metres. Bar Castle at that time was considered the second most powerful after Kamianets, so it was called the "key to Eastern Podillya". Today, there is not much left of the once-powerful fortification: only fragments of bastions that can be seen from the riverside. However, the city authorities have a plan to completely restore their most famous architectural attraction.
The first church was consecrated in the name of St. Nicholas, the patron saint of the Italian city of Bari. Fires twice completely destroyed not only wooden premises but also Church items. In 1807, after the infamous events of the Bar Confederation and the divisions of Poland, on the initiative of the Prior of the Bar Dominican monastery, father Emeryk Shatbeyi, construction of a stone church began. In 1811, the construction of the church was completed. In 1826, Bishop Matskevych consecrated the church. After the November Uprising, the Dominicans were evicted from their monastery and the church remained a parish church. In 1906, the church was significantly built and consecrated in honor of St. Anna, the patroness of the Bar parish.
It was built in the 18th century. The exact date is unknown. It is assumed that this could have happened in 1757, 1760, or 1770, so the Cathedral is one of the oldest buildings in the city. It was built in the Late Baroque style. The Cathedral of Dormition of the Blessed Mother of God has always been the main shrine for the Orthodox from Bar. Until recently, it kept the miraculous icon of Blessed Virgin Mary (original), which was taken from the St. Anne Church. Now the image is located in the new orthodox convent of the city. Another revered icon of the cathedral is the image of St. Nicholas. According to legend, it was brought to the city by Queen Bona Sforza. It was located in the Church of the same name, which was closed later. The Cathedral of Dormition of the Blessed Mother of God in Bar is active after the Second World War.
У середині XVIII століття з волинського Ганнополя до міста прибув отець кармеліт Марек Яндолович, який заснував тут орденський монастир. Встигли збудувати лише корпус келій у стилі бароко, а костел завадили завершити події Барської конфедерації. У царські часи кляштор скасували та передали православному монастирю, для якого у 1908 році звели надбрамну дзвіницю. Приблизно тоді ж з’явилась і Покровська церква, що не дійшла до наших днів. Після відновлення незалежності приміщення пам’ятки віддали римо-католицькому ордену сестер бенедиктинок. Це продовження католицької традиції, адже ще у 1917 році сестра Ядвіга Кулеша заснувала в колишньому покровському монастирі кляштор бенедиктинок.