sentences:  Alefa is named after the historic region to the southwest of Lake Tana, which was the target of a punitive expedition led by Emperor Susenyos in 1608.Based on the 2007 national census conducted by the Central Statistical Agency of Ethiopia (CSA), this woreda has a total population of 170,491, an increase of -20.32% over the 1994 census, of whom 86,350 are men and 84,141 women; 11,639 or 6.83% are urban inhabitants.With an area of 1,961.66 square kilometers, Alefa has a population density of 86.91, which is greater than the Zone average of 63.76 persons per square kilometer.