The main sports Ottomans were engaged in were Turkish Wrestling, hunting, Turkish archery, horseback riding, Equestrian javelin throw, arm wrestling, and swimming. European model sports clubs were formed with the spreading popularity of football matches in 19th century Constantinople. The leading clubs, according to timeline, were Beşiktaş Gymnastics Club (1903), Galatasaray Sports Club (1905) and Fenerbahçe Sports Club (1907) in Istanbul. Football clubs were formed in other provinces too, such as Karşıyaka Sports Club (1912), Altay Sports Club (1914) and Turkish Fatherland Football Club (later Ülküspor) (1914) of İzmir.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What was the leading sport club in 1905?
Galatasaray Sports Club