Very pleasant place to move around. If you are in Bangalore it will be cheapest hill station to visit.It is about 1500 mts above sea level.
The Hill is more like fortified fortress, you can see holes for guns in boundary wall. Actually the hill is Tipu Sultan’s summer retreat. There is nothing much to see other than nature’s beauty and weather. There are small historic buildings but not of such importance except Nehru palace where a SAARC summit has been held in Rajiv Gandhi time. There is a temple, Gandhi nilaya and small play grounds for children. There are small gardens all over the hill.
You can easily go near cliff edges and take your photos in daring poses. There is Tipu’s drop where prisoners are thrown down the hill. I went there in June at that time Pleasant(cool) and strong wind is blowing. I will suggest to wear somewhat more than regular if you plan to come here. A full shirt is enough at that time. You also need to consider that monkeys are always watching you closely.
From Bangalore you can take bus from any bus station like majestic, hosur or hebbal in morning and reach here in around 2 hours. Moving on Nandi hills will not take more that one hour, but enjoy is in staying here as much as you can.
For returning you may not get direct bus to Bangalore so need to go to Chikballapur.