Kothamangalam is a municipality in the eastern part of Ernakulam district in the Indian state of Kerala. The town is in the foothills of the Western Ghats mountain ranges. The highway NH-85 Ernakulam – Madurai – Rameswaram passes through Kothamangalam. Kothamangalam is known as the Gateway of Highrange. Kothamangalam is a part of idukki lokasabha constituency.
Kothamangalam is situated in the eastern part of the Ernakulam district. Kothamangalam is known as the Gateway of Highrange. According to the division of the geographical regions of Kerala, i.e. High-lands, Mid-lands and Low-lands, Kothamangalam is in a Mid-land region. The general topography is hilly. The Munnar hill station is around 85 kilometres from Kothamangalam.
The river Periyar, the largest river in Kerala, flows through the taluk. The dams built across Periyar at Edamalayar, Lower Periyar (near Neriamangalam) and Bhoothathankettu for hydroelectricity generation and irrigation purposes are located in the Kothamangalam taluk. Kothamangalamar, a small river which flows through the town goes to join Kaliyar and Thodupuzhayar to form the Muvattupuzhayar which is the second largest river in Ernakulam district.