 Complete the following phrase:  During the Ottoman rule, many haiduks found refuge in the Balkan Mountains. Close to the highest summit, Botev Peak, is Kalofer, the birthplace of Hristo Botev, a Bulgarian poet and national hero who died in the western Balkan Mountains near Vratsa in 1876 in the struggle against the Ottoman Empire. Also close to Botev Peak is Shipka Pass, the scene of the 