The north-eastern part of the country, around the city of Rostov, was especially hostile to the new faith. Yet, slowly the country began to accept Christian traditions and adopt many of the Christian saints to replace pagan gods. From the outset, the Blessed Virgin Mary became the most sacred, inspiring many icons. One of them - Vladimir Icon of Mother of God - became Russia's all-time symbol. According to Church tradition, it was sent as a gift from Constantinople in the 12th century and has been revered as the greatest shrine of the Russian people ever since. The miracles it performed were described in numerous chronicles and legends. It was said to cure illnesses and ensure rescue from invaders. As time went on, Kievan Rus developed its own church traditions. The first Russian saints were Boris and Gleb. The story goes they were the youngest sons of Vladimir the Great. Well-educated and deeply religious, the princes refused to take part in the family power struggle after Vladimir's death and were murdered on the orders of their stepbrother. Regarded as martyrs, both were canonised by the Russian Orthodox Church in 1071. They are often called "horrorbearers" - the word has become a reference to those Russian saints who suffered physical and moral torture and death because of the anger and treachery of their rivals. One of the most ancient monasteries of Kievan Rus was Kiev Pechersk Lavra. The word "pechera" means cave and "lavra" refers to the highest-ranking monasteries of the Eastern Orthodox Church. The Lavra literally grew out of small underground temples and is also known as the Kiev Monastery of the Caves. It still has a very complex system of narrow underground corridors, along with numerous living quarters and underground chapels. Founded in 1015 in Kiev, it's developed into a key centre of Orthodox Christianity in Eastern Europe. According to chronicles, the monastery was set up by a Greek Orthodox Monk called Anthony, later known as St. Antoniy Pechersky or St. Anthony of the caves. He's venerated as the father of Russian monkhood. Christianity: 1020 years of Russian faith SOURCE: