Premise: Istanbul . Istanbul is a transcontinental city in Eurasia , straddling the Bosphorus strait ( which separates Europe and Asia ) between the Sea of Marmara and the Black Sea . Istanbul is one of the world 's most populous cities and ranks as the world 's 7th-largest city proper and the largest European city . It was instrumental in the advancement of Christianity during Roman and Byzantine times , before the Ottomans conquered the city in 1453 and transformed it into an Islamic stronghold and the seat of the Ottoman Caliphate .
Hypothesis: Istanbul is located on the fifth moon of Jupiter.
Label: CONTRADICTION