Talking about the options to reach Munnar from Bangalore, you have broadly three choices : road, rail and air. The most popular & practical option is by road.
Bangalore to Munnar by Bus
KSRTC (both Kerala's & Karnataka's) operate overnight daily bus services to Munnar from Bangalore. There are also a few private operators with luxury class bus services . Check out Bangalore to Munnar by bus for schedule and online booking details.
Bangalore to Munnar by road:
There are many routes for Bangalore to Munnar, depending on a host of other travel considerations. Here we’ll see a few popular options. Bangalore to Munnar is about 500km drive (about 12 hours ) , with some variations depends on the routes you select. The distance quoted in the following are approximate.
Bangalore to Munnar via Erode: Distance 478km
Bangalore --> 40km --> Hosur --> 50km --> Krishnagiri --> 110km --> Salem --> 60km --> Bhavani --> 20km --> Perundurai --> 42km --> Avanashi --> 22km --> Palladam --> 56km --> Udumalaipettai --> 88km --> Munnar
Bangalore to Munnar via Chamarajanagar: Distance 474km
Bangalore --> 62km --> Kanakpura --> 49km --> Malavalli --> 36km --> Kollegal --> 40km --> Chamarajanagar --> 77km --> Sathyamangalam --> 44km --> Avanashi --> 22km --> Palladam --> 56km --> Udumalpet --> 88km --> Munnar
Munnar from Bangalore via Dindigul: Distance 510km
Bangalore –> 40km –> Hosur –> 50km –> Krishnagiri –> 110km –> Salem –> 93km –> Karur –> 74km –> Dindigul –> 58km –> Periyakulam –> 16km –> Theni –> 16km –> Bodinayakanur –> 50km –> Munnar
Bangalore to Munnar Train:
Munnar doesn't have a direct rail connection. The nearest railway stations from Bangalore is Ernakulam or Coimbatore.
See Bangalore to Munnar by Train for the train options.
Bangalore to Munnar by Air:
The nearest airports for Munnar are Coimbatore (CJB) (in Tamilnadu) and Cochin (in Kerala). However both are good 3 to 5 hours drive further anyway. From Cochin airport Munnar is about 100 km, that is approximately 3 hours drive via Kalady, Perumbavoor, Muvattupuzha, Kothamangalam, Adimali and finally Munnar.
From Coimbatore airport, Munnar is about 5 hours drive (about 160km).
Another option is Madurai airport (IXM), that about 140km from Munnar.
Thanks to the hilly nature of the roads closer to Munnar the driving time is a bit longer for the given distances.
Regarding the choices of flights, Cochin (COK) has better direct connectivity with Bangalore ( about 6 directs flights) whereas Coimbatore and Madurai has flights via Chennai from Bangalore. So that about the itinerary involving the flight connectivity between Bangalore and Munnar.
Kochi and Madurai are nearest airports for Munnar