One of the first places I had visited in New Delhi was the Lodhi Gardens, a beautiful park in Delhi, India that has a lot of tombs and other architectural works dating back to the 15th century.
One of these is the Sheesh Gumbad (“Glass Dome”), an impressive tomb (said to be of Sultan Bahlol Lodi, reigning from AD 1451-89) so named because of the vivid blue tiles used in its façade. Its high dome is characteristic of Lodi architecture, among other features that make it a very good example of that particular period.
Lodhi Gardens is a protected site by the Archeological Survey of India. It is open everyday, no admission fee. Its nearest Metro station is the JLN Stadium.