The cool weather combines with many high mountains, beautiful sightseeings to form the convenient for relaxing tour and discovery tour. Famous sites include Thang Hen Mountainous Lake in Tra Linh, Ban Gioc Fall and Nguom Ngao Cave in Trung Khanh. Among of them, Ban Gioc Fall probably is one of most beautiful waterfall in Vietnam. Several sites where Uncle Ho lived and worked before the August 1945 Revolution include Pac Bo, Coc Bo Cave, Lenin Stream, and Khuoi Nam Stream. In Cao Bang, the traditional festivals have specific characteristics of ethnic groups, for example, Long Tong Festival, Inviting the-Moon-Mother Festival. Less