1. Red Fort (Lal Qila): A UNESCO World Heritage Site and an iconic symbol of India's rich history. 

2. Qutub Minar:  Another UNESCO World Heritage Site, this towering minaret is a stunning example of Indo-Islamic architecture. 

3. Humayun's Tomb: An exquisite garden tomb that served as an inspiration for the Taj Mahal. 

4. India Gate: A war memorial and an iconic landmark in Delhi, particularly beautiful when illuminated at night.  

5. Akshardham Temple: A magnificent temple complex showcasing traditional Indian architecture, culture, and spirituality. 

6. Jama Masjid: One of the largest mosques in India, with impressive Mughal architecture. 

7. Gurudwara Bangla Sahib: A serene Sikh temple known for its beautiful architecture and the langar (community kitchen) that serves free meals to visitors.

8. Nehru Planetarium: An educational center for astronomy and space science.

9. National Rail Museum: An interesting museum showcasing the history of the Indian Railways. 

10. Delhi Zoo: A well-maintained zoo with a variety of animals and birds.