People adjust their gait by interacting with the surrounding environment. Thus, hidden factors in the environment such as fall risk that influence the gait can be exposed by measuring its change during daily walking. For this purpose, in this paper, we employed wearable IMU sensors that enables measurement of stride length and stride time of the pedestrian without environment fixed MoCap system. We also used the GPS receiver for measuring the global position of the pedestrian simultaneously, since the IMU sensors only offer a local change of the gait. The change of the stride length and the stride time were calculated from the IMU sensors and mapped onto the geographic map referring to the GPS data for constructing the Geographical Information System (GIS) of the gait. These gait indices changed according to the type of the walkway, plane, stair, and slope. Also, even in the same walkway, the indices changed by the environmental factors such as obstacles, walking direction and traffic light. The experimental results suggest that measurement of the gait during daily walking in the daily environment seemed to have the potential to expose the factors hidden in the environment such as the fall risk that influence the gait.