If you are interested to see forts, Qutub Minar architecture is must see. KutubMinar is tallest minar in India. Its Height is 237.8 feet. There are 379 steps to climb in minar. Minar was built in 1192. If you want to visit Qutubminar in Delthe address is - Aurobindo Marg, Mehrauli, New Delhi
Central India - Orissa, Maharashtra, Madhya Pradesh forts - Gateway of India, Sanchi, Raigad, Rajgad, Prtapgad, Purandar, Lohagad, Chanderi, Daultabad,Janjeri fort,Shivneri fort
If you are travelling India - Forts, History, Monuments are types of things you must watch. India Trip Guide
has list of cities to visit and places to visit in each city.