![](http://www.alamy.com/thumbs/6/C17CA59C-7D3D-43B8-887F-EAB42E1E633F/2F9838W.jpg)
Byzantine fortress Ustra in Rhodope Mountains
Size: 5616px × 3744px
Location: Zlatograd, Smoljan, Bulgaria
Photo credit: © Cavan Images / Alamy / Afripics
License: Royalty Free
Model Released: No
Keywords: -, autumn, bulgaria, byzantine, cloud, environment, europe, exterior, formation, fort, fortress, grass, highland, landscape, mountain, moutains, natural, nature, outdoor, outdoors, people, plant, rhodope, ruins, scenery, sightsee, sightseeing, sightseer, sky, slope, smoljan, sunbeam, sunrise, tourism, tourist, travel, zlatograd