Alia minar - 2nd minar that did not complete

If you visit Qutubminar , you can also see a second minaret Alai Minar that was abandoned during early stages of construction.
Story is that overly ambition Sultan Ala-ud-Din Khalji dreamt of having a second minar structure that would even double the height of the QutabMinar.
But it could not be materialized. Sultan died and construction was abandoned in very early stages.
What was left - 24.5 meter tall tower base, near to Qutubminar.