This study investigated the relationship between the environmental factor of an urban river setting and activities that occur in the setting. Activities on the water front were defined as getting together for a special purpose and consciously or unconsciously integrating the water front into their life. This study took up the "affordance" (Gibson, 1979) of the river setting as a determinant of water front activities. The purpose of this study was to quantify the water front activities and to estimate the river setting by cluster analysis. Seven types of affordance emerged from the river setting. Zones were divided into two types: those having common behavioral characteristics throughout four seasons and those having different behavioral characteristics for each season. Two types of affordance composition seemed to be discovered from the river setting: one is determined by engineering factors while the other is determined by both engineering and weather factors.
