Manhattan, city (1990 pop. 37,712), seat of Riley co., NE Kans., at the confluence of the Big Blue and Kansas rivers; inc. 1857. It is the trade and processing center of a farm area. Much of the economy is dependent upon Kansas State Univ. and nearby Fort Riley. The Tuttle Creek Dam and reservoir, with numerous recreational areas, is to the north. Damon Runyon was born in Manhattan.