Instead "to" we use the -e dative case suffix in Turkish. Of course this is an -e type suffix and has the -e and -a versions. But this suffix also takes the buffer letter -y if the noun ends with a vowel. 

Example:

İstanbul´a > to İstanbul (has no buffer because ´İstanbul´ ends with a consonant)

Türkiye´ye > to Turkia (has the -y buffer because ´Türkiye´ ends with a vowel)   

Add the correct dative case suffix according to vowel harmony and put the -y buffer when necessary.  The dative case suffix can be -e, -a.