On a regular traffic day it would take about 3½ hours to cover the 130km distance to Munnar from Cochin city.
From Ernakulam city center cross the NH47 bypass (Vyttila bypass) and head towards Tripunithura. And then on to Kothamangalam. Once you've exited Tripunithura town, the city traffic eases and would have a relatively smooth drive all the way to Kothamangalam.
In another 30 minutes you'll reach a small town called Neriamangalam. The road from now on is a starts getting curvy, thanks to the beginning of the high range region. After 30km you'll cross a busy small town called Adimali.
The Kothamangalam to Adimali stretch is scenic route through forest. About halfway between Adimali and Munnar, the rolling tea plantations start appearing on either sides of the road.
At Munnar, NH49 continues to Madurai. Also there is a major road from Munnar heads towards Udumalpet via Marayoor and Chinnar Wildlife Sanctuary.
By the way, if you are driving from north of Ernakulam, you can skip entering Ernakulam city. Take the left diversion (MC Road) at Angamali towards Perumbavoor and Kothamangalam. Or further down on NH47, take the Aluva (Alwaye) to Perumbavoor road that will further take you to Kothamangalam and Munnar.
If you are driving from south of Ernakulam on HH47, take the Aroor bypass. At Maradu or Vyttila take the right diversion to Tripunithura.
Those driving from Kottayam to Munnar will find the Thodupuzha route more convenient.
Munnar is about 130km east of Ernakulam town. NH85 connects Munnar with Ernakulam.
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