The main features of Indo-Islamic architecture

                      The conquest of India by the Muslims made an effective and distinct impact on the indigenous manifestations of life and culture, which gave rise, among other expressions of art, also to a new style in architecture. This style incorporated not only certain new modes and principles of construction but reflected also the religious and social needs of the adherents of Islam.

                       In the Hindu, Buddhist or Jain constructions, spaces were either spanned by beams, or the courses of bricks or stones were laid in corbels, so that the open span was gradually reduced to a size which could be covered with a single slab. Although there exists some evidences to suggest that the true arch may have been known in India earlier, the widely held belief is that the Muslims brought with them the principle of building a true arch, so that the bricks or stones could be laid as voussoirs to reproduce a curve and the space between columns or walls. In any case, even if the true arch familiar to indigenous in ancient times, it was re-introduced by the Muslims and firmly implemented on the soil. The result was flat lintels or corbelled ceilings were replaced by arches or vaults and the pyramidal roof (pidha) or spire (sikhara) by the dome. The necessity of raising a round dome over a square construction introduced multiplication of sides and angles by providing squinches, so that a base with many sides, usually sixteen, could be obtained to raise a circular drum for the dome. A sunshade or balcony was laid on cantilever brackets fixed into and projecting from the walls, which introduced (chhajja) eaves or sun-shade. Brackets with richly curved pendentives, described as stalactite pendentives, lent them fascinating ornamentation when they supported balconies. Kiosks (chhatris), tall towers (minars) and half- domed double portals are some of the other distinguishing features of the Indo-Islamic architecture.

                      The difference in the lay-out of a temple and mosque is explained by the essential difference between the Hindu and Muslim forms of worship and prayer. A cella to house the image of a deity (garbha-griha) and often a small hall in front of the worshippers (mandapa) were regarded adequate for a simple Hindu temple. But the Islamic form of worship, with its emphasis on congregational prayer, requires a specious courtyard (sihn) with a large prayer-hall at its western end (liwan). In the rear of wall of the prayer hall, the centre is occupied by a recess or alcove called (mihrab), and indicates the direction of prayer (qibla). A pulpit (mimbar) to its right is meant for the imām who leads the prayer. A tower or minaret, originally intended for the mu’aḏẖin to call the faithful to the prayer (ma’ḏẖana), later assumed merely an architectural character. A gallery or compartment is sometimes screened off in a corner of the prayer-hall or in some other part to accommodate the ladies who observed purdah. The main entrance to a mosque is on the east and the sides are enclosed by cloisters (riwāqs). A tank (hauz) is provided for ablutions usually in the courtyard of the mosque.

                     The practice of the burial of the dead, as distinct from cremation practise by the Hindus, introduced the tomb. A domed chamber (hujra) with a cenotaph (zarih) in its centre, a mirhab in the western wall, and the real grave (qabr) in an underground chamber (maqbara) constitute the essential elements of a tomb. In larger and more complex tombs, there is also an independent mosque, and in later tombs a well-planned garden. The entrance to the mortuary-chamber is usually from the south.

                          The mode, theme or motifs of ornamentation employed in Islamic buildings are also different from the earlier Hindu vogues. The indigenous ornamentation is largely naturalistic, delineating with a conspicuous zest human and animal forms and the luxuriant vegetation-life characteristic of a tropical country. Among the Muslims the representation of living beings was forbidden by scriptural injunction, and so they took recourse to execution of geometrical and arabesque patterns, ornamental writing and a formal representation of plant and floral life, reflecting in its scantiness the nature of the country where Islam was born.    

                              Lucidity and simplicity of expression, economic use of material and orderly arrangement of different parts characterize the Islamic art, as distinct from the exuberance, richness and exaggeration of the Hindu art. The ornamental designs in Islamic buildings were carved on stone in low relief, cut on plaster, painted or inlaid. Muslim ornamentation, even on stone or other base, in effect is usually close to embroidery. Striking colour effect was often obtained by encaustic enamel on tiles.

                               Lime was known earlier in India, but its use was very limited, mud being used for brickwork, while large blocks of stone were generally laid dry and secured to each other by means of iron clamps. The Muslims on the other hand made an extensive use of lime which served not merely as a binding-medium, but also as plaster and a base for incised decoration and encaustic enamel work.

                         After the initial reaction manifesting itself in the desecration, destruction and spoliation of the earlier Hindu structures the creative monumental activity of the Muslims is marked by two phases. In the first phase, the earlier Hindu temples or other buildings were purposefully demolished and the material used for new improvised buildings. In the later phase, mosques, tombs and other buildings were fully planned and built with appropriate material, which was originally quarried, manufactured or ornamented as necessary. It is in this phase that the Muslim buildings are found at their best.

                         Indo-Islamic architecture falls under three broad classes. The monuments erected by or under the patronage of the Sultans belong to the first class. Contemporaneously, at least in part, monuments were also coming up in the different provinces, which were originally ruled by governors appointed by the Sultans, but which soon declared themselves independent. These exhibit a diversified but distinct class. To the third class belong the constructions of the Mughals, who brought India under an almost united suzerainty.                         

                                   The monuments in Delhi belong to the first and third class. While among important monuments of the first class there exist only two outside Delhi – the Arhai-din Ka-Jhonpra at Ajmer and the Jami-Masjid at Bari Khatu, District Nagaur – Delhi and Agra share between themselves the largest number of monuments erected by or associated with the Mughal rulers.