Ernakulam district covers an area of on the Western Coastal Plains of India. It is surrounded by the Thrissur District to the north, the Idukki District to the east, Alappuzha and Kottayam districts to the south and the Laccadive Sea to the west. The Anamalais occupy a large part of the district, consisting of the forest areas around Pooyamkutty and the Idamalayar Dam. The range also extends into Thrissur, Palakkad, and Idukki districts, as well as Coimbatore and Tiruppur districts of Tamil Nadu. The district is divided geographically into highland, midland, and coastal area. The altitude of the highlands is about . The Periyar River, Kerala's longest, flows through all the taluks except Muvattupuzha. The Muvattupuzha River and a branch of the Chalakkudy River also flow through the district. The average yearly rainfall in the district is . The district has a moderate climate and mostly falls within the Malabar Coast moist forests ecoregion, while the highlands are part of the South Western Ghats moist deciduous forests ecoregion. The Anamudi is the tallest peak in South India, on the border of Ernakulam and Idukki districts. Some parts of the Idamalayar Reserve Forest and Mankulam Forest Division have Sholas but these parts are inaccessible by road. The Idamalayar Reserve Forest, and Edamalakkudy. Many types of sand, soil, and rocks are abundant here. Cochin International Airport is located in the northern part of the district at Nedumbassery, Kochi. The district houses two Urban Agglomerations, Kochi and Kothamangalam. Kochi is the largest city in the state, and 17th most populous in the country according to the Ministry of Housing and Urban Affairs rankings based on the 2011 Census, with an area of over 843km2 and 2.12 million population. Topography The district is divided into three parts: lowland, midland, and the highland that consist of seaboard, plains, and hills and forests respectively. 20 percent of the total area are lowlands. The forests in the eastern part of the district are mostly remote, forming a part of the Anamalais. The highest peak is the Anamudi. The midland consists mainly of plain land and a group of islands that naturally drain water via backwaters and canals. The hilly or eastern portion is formed by a section of the Western Ghats. Muvattupuzha and Kothamangalam taluks, which were initially parts of the Kottayam district and constitute the highlands. Muvattupuzhayar and Periyar are the main rivers, of which the