Sultanate Architecture: The Arcuate Revolution (1206-1526)

Nature: Integration of Islamic structural forms (arch, dome) with Indian decorative motifs (lotus, bell).
Key Feature: The shift from Trabeate (Lintel/Beam) to Arcuate (Arch/Dome) using lime-mortar as a binding agent.

1. Structural Innovations

True Arch: Use of voussoirs (wedge-shaped stones) with a central keystone. First seen in Balban's Tomb.
True Dome: A hemispherical structure supported by squinches or pendentives. First seen in the Alai Darwaza.
Lime Mortar: Enabled the construction of massive, vaulted ceilings and wide-span domes.

Mamluk Style: Reused material from Hindu/Jain temples (e.g., Quwwat-ul-Islam mosque).
Khalji Style: High point of artistic finesse; red sandstone with marble inlay. The Alai Darwaza is the finest example.
Tughlaq Style: Austere and military-like; use of Batter (sloping walls) for strength. Gray sandstone was preferred.
Lodi Style: Introduction of the Double Dome (e.g., Sikandar Lodi's Tomb) to correct optical illusions and provide internal/external proportionality.

1st True Arch: Many students confuse it with the Qutub Minar complex; it is actually found in Balban's Tomb.
The Minar: The Qutub Minar was not just a victory tower but a Mazina (place for the muezzin to call for prayer).
Decoration: Unlike European churches, Islamic structures avoided living figures; decoration relied on Calligraphy, Geometry, and Arabesque (floral patterns).