By road is the main and only approach that takes you directly to Thekkady. The two options when reaching by road are by bus and by car. There are Kerala State Department buses to Thekkady from a bunch of cities, including important travelling destinations such as Kochi, Kottayam and such. These buses are usually fairly comfortable and easy to travel in.
Thekkady can also be reached in cabs and self driven cars. With respect to cabs, they are also available from a number of places and cities in Kerala. However, they tend to be a little expensive. going by road to Thekkady is not a bad idea as the routes into this heavily forested area are scenic and worthy of travelling. By road, it’s a 4-5 hour journey from Kochi, around 160 kms. A drive from Bangalore is also possible as the route is roughly 9 hours long and some 510 kms long, coming through Karnataka and passing towns like Dharmapuri and Dindigul.
There are other routes available as well. However, they are both at least 50-60 kms longer. When driving to Thekkady, it is advisable to carry a certain amount of petrol/diesel with you as there are not that many fuel stops around. Also, inside Kerala, the roads can be tricky as they are in dense forest and rural areas. This is also something that needs to be noted when driving there.