Air pollution is a serious threat to the planet. The faster an economy grows, the more it pollutes the atmosphere. It's not just the cars and factories, the burning of solid fuels in developing countries also contributes to the problem. In fact, the way things are headed, everybody in big cities will be forced to wear gas masks in the near future. According to a recent survey by the World Health Organisation (WHO), 15 Indian cities feature in the top 30 most polluted cities in the world. In other words, half of the most polluted places on the planet are in India. This is a major cause for concern for everyone.

8. Agra

Home of the Taj Mahal, the main reason for the pollution here is the dust that flies in when the Yamuna runs dry. Large scale mining, industries and mining also add to the pollution.

7. Allahabad

The second oldest city in India is home to Prayaga, the oldest shrine in Hinduism. This city is also where the Ganga and Yamuna meet. Just like Amritsar, Allahabad also sees a lot of pilgrims