Theory:

Konark, Sun temple was built in the \(13^t\)\(^h\) century and is an example of Oriya architecture. This temple is dedicated to Lord Surya and is thought to have been constructed by King Narasimhadeva \(I\) of the Eastern Ganga Dynasty.
 
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Sun Temple, Konark
The temple is built like a colossal chariot, with ornately carved stone wheels, pillars, and walls. A substantial portion of this Indian archaeological site is still in ruins. The temple has been listed as a UNESCO World Heritage Site.
 
Red Fort, Delhi
  
Since 1648, when the fifth Mughal Emperor, "Shah Jahan", decided to move his empire's capital from Agra to Delhi, the Red Fort has served as the Mughal rule's official headquarters. The Red Fort, built of red sandstone, is one of the Mughal period's most significant marvels. It was notified as a UNESCO World Heritage Site in 2007.
 
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Red Fort is situated in Delhi

Sanchi, Madhya Pradesh - The land of the Stupas
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Buddhist Stupa situated in Sanchi

Sanchi'sBuddhist monument is one of India's oldest stone buildings. UNESCO named this as a World Heritage Site, and Emperor Ashoka of the Mauryan dynasty founded the Great Stupa in the \(3^r\)\(^d\) century \(BCE\). This archaeological site in India contains sculptures and monuments that are excellent examples of Buddhist art and architecture creation. The stupa is situated at the top and surrounded by gardens, providing tourists with peace and serenity.
 
9. Brahadeeshwara Temple, Tanjore - Chola Temple:
 
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Chola master piece- Brahadeeshwara Temple, Tanjore
 
The Great Living Chola Temples is a unique archaeological site in India. These are regarded as an evolutionary landmark in the architecture of Southern India.
 
10. Humayun's Tomb, Delhi - Archaeological site in India made of red sandstone:
 
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Humayun's Tomb, Delhi
 
Humayun's Tomb was known for its stunning architecture and the first garden-tomb of the Indian subcontinent. It was declared as World Heritage Site in 1993 by UNESCO and has undergone widespread restoration work. Between \(1569\) and \(1570\), Humayun's son Akbar constructed the Tomb, which is also the first building to use significant amounts of red sandstone.
Reference:
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https://www.holidify.com/images/cmsuploads/compressed/BrihadishwaraTemple_20180314111033.jpg
https://www.holidify.com/images/cmsuploads/compressed/Humayun-tomb_20170809201316.jpg