Main Eastern Highway, the second longest highway in Kerala after M C Road, connects Punalur in Kollam District with Muvattupuzha in Ernakulam District. The highway spans across the districts of Kollam, Pathanamthitta, Kottayam, Idukki and Ernakulam and touches some major cities and towns on the way.
Main Eastern Highway originates at Punalur (starts from km 44/900 of National Highway 208) and runs north-west touching Mukkadavu to join State Highway 5 at Pulimukku junction near Pathanapuram.
Past Pathanapuram, the road enters Pathanamthitta District and continues its way north through Koodal junction, Konni, Makkapuzha and Ponthanpuzha before entering Kottayam District. Mamarakolenji and Angadi are the other towns lying along the Main Eastern Highway in Pathanamthitta.
In Kottayam, Manimala is the first major settlement lying near the Main Eastern Highway. Across the Manimala bridge and the road continues its way north touching Cheruvally, Ponkunnam junction (K K Road (SH 13) crosses and overlaps for 0.4 km), Elamkulam, Pala and past Kadanad to eventually enter Idukki District.
In Idukki, Nellapara is the first settlement one would come across, while traveling along the Main Eastern Highway from Kottayam. Beyond Nellapara, the highway runs past Thodupuzha and then turns north-west to enter Ernakulam District.
In Ernakulam, the highway runs north through Vazhakulam, Anikad and Perungala before ending at Muvattupuzha, on the M C Road. Muvattupuzha is 59 km east of Ernakulam.