The modern town of Ghazni is a pale shadow of its former glory. In the 11th century, the city was home to the Ghaznavid empire. Sultan Mahmud filled his court with poets and artists, his stables with elephants, and whenever the treasury was bare, he raided Delhi, introducing Islam to India in the process.
Ghazni's most visible monuments to this history are it's two massive 11th-century minarets on the road from Kabul. Mahmud's tomb lies nearby.