Kolli Hills or Kolli Malai (Tamil: கொல்லி மலை) is a small mountain range located in Central Tamil Nadu.
Flora and fauna
Kolli Hills or Kolli Malai (Tamil: கொல்லி மலை) is a small mountain range located in central Tamil Nadu in Namakkal district of India. The mountains are about 1000 to 1300 m in height and cover an area of approximately 280 km². The Kolli Hills has 70 hair pin bends to reach the top of the hills. The Kolli Hills are part of the Eastern Ghats, which is a mountain range that runs mostly parallel to the east coast of South India. The mountains are relatively untouched by commercial tourism and still retain their natural beauty.
From chennai, you have travel towards salem. After crossing chinna salem, you should take a left at attur town. Till Attur it's a four lane highway. After that its hardly 60-70 kms to kolli hills.
There is a nominal vehicle fee (Rs.10/bike & Rs.20/car) collected by the temple committee for visiting the temple and waterfalls. There will be an additional Rs.10/visitor at the falls' entry.
The place is very underdeveloped in terms of traveler's convenience. Very few lodging options, eat-outs and very few places to see. The climate is the best factor. You can relax, lay back and enjoy the nature.
There is a Indian Oil petrol bunk opened near Semmedu village. Also there are KVB and Indian Bank ATM's in the same village
Fresh fruits are the main attraction. You can get fresh pineapple, tapioca, jack fruit. There is one decent non-veg hotel and numerous veg hotels. Naatu Kozhi Varuval (Country Chicken Roast) is a local favorite.
There are TASMAC liqour shops in Semmedu and Solakaadu towns. They stock some decent branded liqours.
Good lodgings and resorts are scarce. Nallathambi Resorts  should be preferred for a family stay. There are other small lodgings and mansions, available at a low rate. But service and cleanliness is not commendable. When planning for a weekend stay, make sure you book early.There is a new homestay opened, made of ecofrindly wooden cottages by name "Kolli Hills Camp", near Thembalam arch.
There are absolutely no street lights outside town. The towns sleeps by 8pm.