In this research, we tried to clarify which kind of objects or situations are preventing adventitiously blinded people from smooth walking in daily walking environment. Ten adventitiously blinded people are asked to walk independently in environments which they are fully accustomed to and have little difficulty to walk. Their walking behavior are recorded by video camera and analyzed. The results are as follows: 1) Adventitiously blinded people tend to walk on ether side of street, where there are objects such as power poles and bicycles which could be serious obstacles. 2) When walking on sidewalks, sometimes adventitiously blinded people happen to wander into parking lots or open spaces. 3) Tactical tiles, which are basically guiding adventitiously blinded people's walking, are sometimes very difficult to follow, because surrounding ground's surface is very similar to tactical tiles.
