Dept. of History, US Military Academy published on 02 June 2013
An illustration of the Long Walls fortifications which connected the city of Athens to its port of Piraeus from the 5th century BCE.
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Original image by Dept. of History, US Military Academy. Uploaded by Mark Cartwright, published on 02 June 2013 under the following license: Creative Commons: Attribution-ShareAlike. This license lets others remix, tweak, and build upon your work even for commercial reasons, as long as they credit you and license their new creations under the identical terms.