The Gangetic Plains

South of the Himalayas lie the huge, fertile Gangetic Plains (also called the Northern Plains). They have been at the heart of India's history and civilisation.

Why so fertile? Follow the chain:

• Himalayan snow melts →
• rivers (Ganga, Indus, Brahmaputra and their tributaries) carry water and minerals down →
• the soil becomes rich →
• farming thrives (lots of rice and wheat).

The mountains didn't just stand beside the plains; they built them.

Rivers also make electricity. And because the soil feeds so many, a large share of India's people live here.

The land is flat, so it's easy to build roads and railways that carry people and goods a long way. And for thousands of years the rivers themselves were highways for travel and trade.

Most rivers are named after goddesses: Ganga, Yamuna, Kaveri. But Brahmaputra means son of Brahma.

A puzzle: the Brahmaputra gets bigger in summer instead of drying up. Why? (Hint: what happens to Himalayan snow in summer?) And look at a satellite photo of India at night: why are the lights so crowded over the plains?