If one day you visit Istanbul one of te places you have to visit will be BASILICA CISTERN…it was built by Byzantions on 5h century for keeping the water supplies safely. It is a pool in fact. The Byzantions were getting their water from rivers around the city to that pool to keep for hot seasons.
It is located at SULTANAHMET area where Blue Mosque and HAGIA SOPHIA Museums are by walk 5 minutes.
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