According to historical sources modern Kandahar was
founded (or renamed) by Alexander the Great around 330 a.C., it is posible that
the toponim <Kandahar> is his historical related to <Alexandria>,
for example:
Alexandria > *Al-Ksandar > *Al-Kandsar >
*Kandasar > Kandahar
(This chain is just an imagitive one, I don't
consider it seriously!)
Davius Sanctex