The Gates of the Sixth City of Delhi were constructed by Sher Shah Suri who reigned between 1538 and 1545 near the Old Fort or Purana Quila in 1534 that lies near Chandni Chowk in Old Delhi. There were four gates built on the Northern side, Southern side and Western side of the Old Fort standing tall at a height equivalent to a double storied building made of red sandstone with Chhatris and high Ceilings.
The City was established after Emperor Sher Shah Suri demolished the ancient city of Humayun named 'Dina Panah' and built a beautiful fort which stretches over 2 km in length in an oblong pattern and adorned with Bastions. The western gate named the 'Bara Darwaza' or the 'Big Gateway' forms the primary entry point into the fort, the Northern gate named 'Talaq Darwaza' was built between 1543 and 1544 for unknown reasons and is adorned with a tall archway within which there are two smaller arched openings. The outer surface is decorated with coloured tiles and the inner rooms in the second floor have smooth plaster work done over it.
The Old Fort was left incomplete by Emperor Suri and later completed by Emperor Humayun after he reclaimed the Delhi Throne and hence, the gate on the southern end is named 'Humayun Darwaza' in honour of the Emperor either because it was built by Humayun or because it overlooks his Tomb. This gate has an inscription that refers to the rule of Sher Shah Suri between 1543 and 1544.
The Sher Shah Gate lies towards the south of Khairu'l Manazil Mosque which is known to be the original entrance to the City of Delhi. It is made from red sandstone and the second storey is covered in grey quartzite and hence, this gate is also named as the 'Lal Darwaza' or 'Lal Gate' where 'Lal' means 'Red' and the government has sanctioned over 75 lakhs to ASI for the extensive renovation and conservation of this gate and its surrounding areas.