Munnar doesn't have a direct rail connection. If you are thinking of rail connectivity, it still involves some 150km of road travel to Munnar.

Take any of the Ernakulam bound trains from Bangalore. Travel further to Munnar by Road.Bangalore to Ernakulam is about 11 hours travel by train. Further road journey to Munnar is about 4 hours.

There are three daily trains and a few more weekly/triweekly trains connecting Ernakulam with Bangalore.

Get down at Ernakulam (ERS or ERN station). Or at Angamali (AFK) or Aluva (AWY) ahead of the Ernakulam Town (ERN) station.

From Alway or Angamali, practically you will save some 30km road distance as compared to traveling from Ernakulam to Munnar. However Ernakulam is a large city where you can get better options for the road travel to Munnar.

Note, there are two railway stations in Ernakulam. Some trains travels via both, some not. Ernakulam Junction (Station code:ERS), popularly called the south railway station is close to the KSRTC bus station. Ernakulam Town (Station Code : ERN), locally called the north station is about 4km north of the Eranakulam Jn.

In either way you can opt for private buses of the state operated (KSRTC) to Munnar. The route followed from Ernakulam is :Ernakulam -> Vyttila -> Thrippunithura -> Kolencherry -> Muvattupuzha -> Kothamangalam -> Adimali -> Aanachaal -> Munnar.

If a direct bus is not available readily, you can explore the possibility of a bus service to an intermediate point, most likely to Kothamangalam. From Kothamangalam you can get a bus connection to Munnar.

Similarly , if you are getting down at Angamaly or Alwaye (Aluva) ,the bus route to be followed is : Angamaly, Kalady, Perumbavoor, Kothamangalam, Adimali, Anachal, Munnar. Here again, if a direct bus is not available, catch one to an intermediate point. Both Angamali and Alwaye has bus stations.

Of course you can hire a cab from Aluva, Angamali or Ernakulam for Munnar. So that’s about the train options for Munnar from Bangalore.

By the way, the Ernakulam to Munnar route is one of the most scenic ghat roads in southern India.

Via Coimbatore :

There are three daily trains from Bangalore To Coimbatore – The Coimbatore Express (Train No.1013), Kanyakumari Express (Train No: 6526) and the Ernakulam Express ( Train No. 2677). Trains take about 7 hours to reach Coimbatore from Bangalore. Further take the road connection from Coimbatore to Munnar.

There are some direct bus services to Munnar from Coimbatore. If that is not available catch a bus to Udumalpet. Go the Ukkadam bus stand in Coimbatore city for bus connections. There are frequent buses (private and state run) from Coimbatore to Udumalpet.

Coimbatore to Udumalpet bus journey is about 1.5 hours to 2 hours. From Udumalpet you can get a bus to Munnar (leaves in every 1 hour or so). Udumalpet to Munnar is about 3.5 hours by bus. So it is roughly a 5 to 6 hours affair getting you to Munnar from Coimbatore by bus.

Also check out the other options to travel from Bangalore to Munnar.