Buland Darwaza is an architecturally rich structure and made of red and buff sandstone and decorated with white and black marble. It's a great monument to witness the architecture of Mughal period and admire the civil engineers of ancient times.
Buland Darwaza is a part of Fatehpur Sikri Fort. The Fatehpur Sikri was the Mughal empire capital for around 12-15 years (around 1570-1585), when Mughal Emperor Akbar shifted his capital from Agra to Fatehpur. But later due to the shortage of water, he had to shift the capital back to the Agra.