The India Gate is a war memorial and one of Delhi's most famous landmarks. The best time to visit is early in the morning, when the area is relatively quiet. You can take a walk around the monument or sit on the lawns and enjoy the view.
The Red Fort is a UNESCO World Heritage Site and was the main residence of the Mughal Emperors. It's a majestic fort with beautiful architecture. There are also museums and galleries within the fort, which are worth visiting.
The Qutub Minar is another UNESCO World Heritage Site and is the tallest brick minaret in the world. It has beautiful carvings and is surrounded by other historical buildings and ruins. You can also visit the nearby parks and gardens.
Chandni Chowk is one of the oldest and busiest markets in Delhi, famous for its street food and shopping. You can explore the narrow lanes and alleyways, visit the historical Jama Masjid, and enjoy the local delicacies. The market is closed on Sundays.
The Sarojini Nagar Market is a popular market in south Delhi that offers a great shopping experience at reasonable prices. You can find clothes, accessories, footwear, and much more here. The market is closed on Mondays.
The Lotus Temple is a Bahá'í House of Worship and a beautiful modern monument with a unique architecture. It's shaped like a lotus flower and is surrounded by pools and gardens. You can enjoy the serene atmosphere and participate in the prayers and meditation sessions.
If you have more time, you can also visit some other famous landmarks like Humayun's Tomb, Akshardham Temple, and the National Museum. If you have less time, you can skip some of the places and spend more time at others. Make sure to carry water and comfortable shoes for walking. The best way to travel within Delhi is by the metro as it's fast, cheap, and convenient. Avoid carrying too much cash and be cautious of pickpockets in crowded areas.