SACRED CITIES OF THE WORLD: Angkor Wat, the Lost City of Ghosts. From the 9th to the 13th centuries the Khmer Emperor ruled his vast empire that included Cambodia, Laos, Thailand, and large parts of Vietnam from his capital city of Angkor Wat. Monumental stone temples, palaces, public buildings, and suburbs spread for miles around, making Angkor Wat one of the largest cities in the medieval world. In the year 1431 the empire was invaded by a coalition of kings of Thailand and Angkor Wat was looted and burned. Join Dr. Ronald Brown for this virtual exploration of a former empire. Sponsored by the Friends of the Library. 3 p.m.