narrow strip of coastland, southwestern India, fronting the Arabian Sea to the west and constituting almost all of Kerala state and most of the Malabar Coast. Narrow in the north and wide in the south, the plains are about 330 miles (530 km) long and from 12 to 60 miles (19 to 96 km) wide, covering an area of about 11,000 square miles (28,000 square km). The plains are indented by numerous shallow lagoons, known as kayes, that are formed by teris (sand dunes). The sandy beaches are covered with coconut palms. According to the Purana (a collection of Hindu literature), the region, also known as Parashurama Kshetram, was reclaimed from the sea by the sage Parashurama. The Kerala Plains lie below 33 feet (10 metres), with hills of the Western Ghats, the Nilgiri, and the Southern Ghats to the east.

Many streams crisscross the plains and serve as inland waterways, constituting about one-fifth of India's total length of waterways. The Periyar River is the most important river that crosses the plains. About half of the land is under cultivation, mainly planted with rice and cassava (manioc). Sugarcane, ginger, ragi (cereal grass), peanuts (groundnuts), and sesame seeds are also grown. Cash crops include coconuts, pepper, betel nuts, cardamom, rubber, coffee, and tea. Cashews, tea, and fish are processed; cement, aluminum, rayon, and electrical goods are manufactured; and coir, plywood, and paper are made.

The plains are densely populated, and Malayalam (Malayalam language), an offshoot of Tamil, is the local language. The chief cities include Kochi, Thiruvananthapuram, Kozhikode, Alappuzha, Thrissur, and Kollam.