ality . ▁Ker ch ▁was ▁a ▁center ▁of ▁trade ▁between ▁Russia ', ▁Crime a , ▁C au cas us ▁and ▁the ▁Orient . ▁ ▁In ▁the ▁ 1 3 th ▁century , ▁the ▁Crime a ▁including ▁Kor chev ▁was ▁inv aded ▁by ▁Mong ols . ▁After ▁Mong ols , ▁the ▁city ▁became ▁the ▁Gen o ese ▁col ony ▁of ▁Cer co ▁( Ch erk io ) ▁in ▁ 1 3 1 8 ▁and ▁served ▁as ▁a ▁sea ▁har bour , ▁where ▁town spe ople ▁worked ▁at ▁salt - works ▁and ▁fish ery . ▁ ▁In ▁ 1 4 7 5 , ▁city ▁was ▁passed ▁to ▁the ▁Ott oman ▁Empire . ▁During ▁the ▁Turkish ▁rule ▁Ker ch ▁fell ▁into ▁decay ▁and ▁served ▁as ▁a ▁slave - market . ▁It ▁repeatedly ▁suffered ▁from ▁ra ids ▁of ▁Z apor iz h ian ▁C oss acks . ▁▁ 1 8 th ▁– ▁ 2 0 th ▁centuries ▁In ▁response ▁to ▁strength ening ▁of ▁Russian ▁military ▁forces ▁in ▁Az ov ▁area , ▁the ▁Tur ks ▁built ▁a ▁for tr ess , ▁named ▁Y en ik ale , ▁near ▁Ker ch ▁on ▁the ▁shore ▁of ▁Ker ch ▁Stra it . ▁The ▁for tr ess ▁was ▁completed ▁by ▁ 1 7 0 6 . ▁In ▁ 1 7 7 1 ▁the ▁Imperial ▁Russian ▁Army ▁inv aded ▁Crime a ▁and ▁approached ▁Y en ik ale . ▁The ▁Tur ks ▁decided ▁to ▁abandon ▁the ▁for tr ess , ▁though ▁rein for c ements ▁from ▁the ▁Ott oman ▁Empire ▁had ▁arrived ▁a ▁few