Origins: This picture depicting a roundabout bridge has thrown many viewers for a loop. It must be a manipulated image, most reason, because there's no obvious reason for a structure like this to exist — why go to all the additional trouble and expense to construct a round bridge when a much shorter, conventionally straight one would have served the purpose of spanning the river below just as well?
Nonetheless, the structure is real, and its unorthodox shape is due to the fact that it wasn't built solely for the strictly functional purpose of conveying traffic across a river.
This bridge is part of the Hiyoshi Springs resort in Nantan, Japan. Hiyoshi Springs is adjacent to the Hiyoshi Dam, and
the resort's circular Friendship Bridge is located at the foot of that dam. The bridge, which has an 80-meter diameter, was designed by modern Japanese architect Norihiko Dan and offers a pathway for pedestrian foot traffic which provides both a means of crossing the river and spectacular views of the dam, river, and surrounding landscape in all directions.
The Friendship Bridge can be viewed from above through Google Maps, and additional images of it can be found on various Internet sites: