A recent ranking of India's cities by air quality has been reported. Surat has achieved a notable position, entering the top five clean-air cities. In contrast, Delhi and Mumbai have fallen outside the top 20.

Further information on this ranking is available from the source. The details of the ranking and the factors that contributed to Surat's position are not specified here.

Readers can refer to the source publication, GujaratSamachar English, for more details on the clean-air city rankings and the performance of various cities, including Surat, Delhi, and Mumbai.