Kochi (state Kerala, country India) is the closest airport. Drive down to Munnar, where you can find lodging and Kolukkumalai is a day trip by 4x4 vehicle.
At Kolukkumalai, tea is grown at an altitude of around 8000ft. This is world's highest grown tea. And the best part, the processing it done at the top of the hill at around 7500ft, in factory built in the 1930s. The drive up to the top of the mountain is the craziest experience you will ever have. You have rent a 4x4 jeep, which take almost 1.5 hrs to cover single lane mud/stone road up to the top. The distance is only 15Kms, extremely bumpy and when you see another jeep coming from the opposite direction and you see your driver backing up - you pretty much freak out! But one look at the scene around you, you lift up the camera, start taking pictures and forget all about the jeep which even if it were to get off the road wouldn't roll down all the way because, we were told that, the tea plantation is strong and good roots, it can easily hold a truck.