who built it?
Architect Ustad Ahmad Lahori, under  Emperor Shah Jahan
Red Fort
Emperor Shah Jahan commissioned 
construction of the Red Fort on 12 May 1638, when he decided to shift his capital from Agra to Delhi. Originally red and white, its design is credited to architect Ustad Ahmad Lahori, 
where was indian flag hoisted on 15 august 1947 At the Lahori Gate of the Red Fort in Delhi how is this day celebrated? On the eve of Independence Day, the President of India delivers the "Address to the Nation",  the Prime Minister hoists the Indian flag on the ramparts of the historical site of Red Fort in Delhi, twenty-one gun shots are fired in honour of the solemn occasion how did the above mentioned fort get its name? Its English name "red fort" is a translation of the Hindustani लाल क़िला, deriving from its red-sandstone walls
wiki:12480245
Red Fort [SEP] Introduction
The Red Fort is a historic fort in the city of Delhi (in Old Delhi) in India that served as the main residence of the Mughal Emperors. Emperor Shah Jahan commissioned construction of the Red Fort on 12 May 1638, when he decided to shift his capital from Agra to Delhi. Originally red and white, its design is credited to architect Ustad Ahmad Lahori, who also constructed the Taj Mahal. It was constructed between May 1639 and April 1648. On 15 August 1947, the first prime minister of India, Jawaharlal Nehru, raised the Indian national flag above the Lahori Gate.