The great fortress of Rumeli Hisari was built at the order of Sultan Mehmet the Conqueror in the 15th Century. It sits at the narrowest part of the Bosphorous Strait, and was originally intended to control shipping traffic in preparation for the siege of Constantinople.
Mehmet knew ships allied to the Byzantine armies would be travelling up the strait to supply goods, and he wanted to curtail any chance of this happening with his great fortress.
Mehmet had a novel idea for motivating his generals to complete the structure in the fastest time: he dared them to be first to complete each tower or wall, promising lavish rewards in return. The scheme worked, and the enormous fortress was completed in just four months.
However, the imposing fortress'military life lasted for only a year. Mehmet's forces conquered the Byzantine capital in record time, so there was no need for this military post.
The fortress was used for a while as the world?s most elaborate toll booth, before becoming a barracks, a prison and then finally an open-air theatre.
Today, it's used as a venue for outdoor concerts and plays, and the public is welcome to visit and wander around its walls. Rumeli Hisari is open every day except Wednesdays, from 9am to 4.30pm.
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