The second largest city on Earth is Delhi, India. It is a large city with a population of over 28 million people. Delhi is known for its rich history and cultural landmarks, such as the Red Fort and Jama Masjid. It is also a major commercial and economic center, with a thriving business district and bustling markets. Despite its size and importance, Delhi is often overshadowed by Mumbai, which is the largest city in India and the 4th largest city on Earth. However, Delhi is a fascinating and dynamic large city in its own right, and is definitely worth a visit for anyone interested in exploring the diverse and vibrant culture of India.