Delhi, the capital of India, is a city with a rich architectural heritage. Some of the prominent architectural sites in Delhi are:
Qutub Minar:

It is an iconic monument and a UNESCO World Heritage Site, located in the Mehrauli area of Delhi. It is a 73-meter-tall brick minaret, with five stories and intricate carvings and inscriptions. The Qutub Minar was built in the early 13th century by Qutub-ud-din Aibak, the first Sultan of Delhi, and is believed to have been constructed to commemorate the victory of the Muslim armies over the Hindu Rajputs. The minaret is surrounded by several other ancient structures, including the Quwwat-ul-Islam Mosque, the Iron Pillar of Delhi, and the Alai Darwaza.
Humayun’s Tomb:

This magnificent tomb is located in the Nizamuddin East area of Delhi and was built in the mid-16th century by the Mughal Empress Bega Begum, for her husband Emperor Humayun. The tomb is a UNESCO World Heritage Site and is known for its Persian-style architecture, which includes intricate carvings, beautiful gardens, and a central dome. The Humayun’s Tomb is considered to be one of the finest examples of Mughal architecture in India and served as a prototype for the later Taj Mahal.
Red Fort:

This iconic fort, also known as Lal Qila, is in Old Delhi and was built by the Mughal emperor Shah Jahan in the mid-17th century. The fort is a UNESCO World Heritage Site and is known for its beautiful red sandstone walls, massive gates, and impressive architecture. The Red Fort served as the residence of the Mughal emperors for almost 200 years and is known for its rich history and cultural significance.
India Gate:

It is a war memorial and popular tourist spot located in the heart of Delhi. The India Gate was built in the early 20th century to commemorate the Indian soldiers who died in World War I and is surrounded by beautiful gardens. The arch-shaped monument is made of red sandstone and stands at a height of 42 meters. It is also known as the All-India War Memorial and is considered to be one of the most important national monuments in India.
Jama Masjid:

It is one of the largest mosques in India and is located in the Old Delhi area. The mosque was built in the mid-17th century by the Mughal emperor Shah Jahan and is known for its beautiful architecture and intricate designs. The Jama Masjid has three large domes and two minarets and can accommodate up to 25,000 worshippers at a time. The mosque is also known for its historical and cultural significance and is a popular tourist spot in Delhi.
Lotus Temple:

It is a modern architectural marvel located in the southern part of Delhi. The Lotus Temple is a Bahai House of Worship and is known for its unique lotus-shaped structure, which is made of white marble. The temple has won several architectural awards and is surrounded by beautiful gardens and pools. The Lotus Temple is open to people of all religions and is a popular tourist attraction in Delhi.
Akshardham Temple:

It is a magnificent temple complex located on the banks of the Yamuna River in Delhi. The Akshardham Temple is known for its beautiful architecture, intricate carvings, and serene atmosphere. The temple complex is dedicated to Lord Swaminarayan and features several structures, including the main temple, an exhibition hall, and a musical fountain. The Akshardham Temple is a popular tourist spot in Delhi and attracts visitors from all over the world.
Safdarjung’s Tomb:

It is a historical monument located in the heart of Delhi and was built in the mid-18th century. The tomb was constructed by the son of the Mughal emperor Aurangzeb, in memory of his father’s prime minister, Safdarjung. The tomb is known for its beautiful architecture, which includes intricate carvings, arches, and domes. The tomb is surrounded by lush gardens and is a popular tourist attraction in Delhi.
Raj Ghat:

It is a memorial to Mahatma Gandhi, located on the banks of the Yamuna river in Delhi. The Raj Ghat is a simple black marble platform, with an eternal flame burning at one end. The memorial is surrounded by beautiful gardens and is a popular spot for tourists and locals alike. The Raj Ghat is a place of great significance to the people of India and is visited by thousands of people every year.
Parliament House:

It is an iconic building located in the central part of Delhi and is the seat of the Indian parliament. The Parliament House was built in the early 20th century and is known for its impressive architecture, which includes a circular structure with a central dome. The building is surrounded by beautiful gardens and is a popular tourist attraction in Delhi.
Purana Qila:

It is an ancient fort located in the heart of Delhi, and is believed to be one of the oldest forts in India. The Purana Qila was built by the Mughal emperor Humayun in the 16th century, but the site has a history that dates back to the 3rd century BC. The fort is known for its massive walls, beautiful architecture, and several important structures, including the Sher Mandal, which was built by the Mughal emperor Babur and is believed to have been his library.
Tughlaqabad Fort:

It is a ruined fort located in the southern part of Delhi and was built in the 14th century by the Tughlaq dynasty. The Tughlaqabad Fort is known for its massive walls, which were designed to protect the fort from enemy attacks. The fort also features several structures, including the mausoleum of Ghiyas-ud-din Tughlaq, who was the founder of the Tughlaq dynasty. The Tughlaqabad Fort is a popular tourist attraction in Delhi and is known for its historical and cultural significance.
Jantar Mantar:

It is an astronomical observatory located in the heart of Delhi and was built in the early 18th century by the Rajput king Sawai Jai Singh II. The Jantar Mantar is known for its unique architecture, which includes several massive astronomical instruments, such as the sundial, the equatorial dial, and the meridian circle. The observatory is a popular tourist attraction in Delhi and is known for its scientific and historical significance.
Each of these architectural sites in Delhi has its own unique history, cultural significance, and architectural style, making the city a fascinating destination for architecture enthusiasts and history buffs.