The Gol (Round) Gumbaz (Dome) is the mausoleum of Muhammad Adil Shah (r. 1627-1656) of the Adil Shahi dynasty of Bijapur. It appears to have been the desire of the ruler to build a mausoleum that was comparable to that of his father, Ibrahim Adil Shah II. Since his father's mausoleum, known as the Ibrahim Rauza, was exceptional in composition and decoration, the only means of avoiding direct competition was through size.
It is one of the biggest single chamber structures in the world and covers an area of 18,225 square feet (1,693 square meters), which is bigger than the better known Pantheon in Rome which is 14,996 square feet (1,393 square meters). The mausoleum is part of a complex that includes a mosque, a dharmshala (inn for travelers) and other buildings related to the sovereign's mausoleum. The building was never properly completed as intended since construction began towards the end of Muhammad Adil Shah's reign. As a result, the tomb is a plain cube with towers on each corner.
Built of dark grey basalt and decorated plaster, the walls are nine feet (2. 7 meters) thick and 100 feet (30. 5 meters) in height. The interior measures 135 feet (41 meters) on each side. Each exterior face of the cube displays three great blind arches. The central arch is wider than the others and is dressed with wooden panels with small rectangular entrance and three rows of arched windows punched through. Above the south door or main entrance, hanging from a chain from the cornice, is a 'bijli patthar' (meteorite) that is said to have fallen during Muhammad Adil's reign. It's believed the stone guards the tomb from lighting.
The cornice and parapet of the cube is the most articulated feature of the facade. The cornice rests on highly carved stone corbels that project about ten feet (three meters) from the wall. The cornice supports the parapet which has a row of arched openings and leaf-shaped merlons. In the center of the tomb chamber is a platform with the cenotaphs of Muhammad Adil, his youngest wife Arus Bibi, his favorite daughter and a grandson. The main cenotaph is marked by an elaborate wooden baldachin. The real tombs are located below in the basement and are accessed by a staircase under the western entrance.
An octagonal chamber was attached to the central arch of the north facade at a much later date. According to some the octagonal chamber was meant to shelter the remains of Jahan Begum, wife of Muhammad Adil, but this would have been contrary to the convention of the wife's grave situated next to the husband's. Most likely, it could have been for the spiritual mentor of Muhammad Adil. The corner towers are incongruous with the rest of the mausoleum composition. They are divided into seven floors with a projecting cornice and a row of arched openings marking each level.
Combined, the towers resemble Chinese pagodas more than minarets. Each tower is then capped by a majestic hemispheric dome with a ring of carved leaves around the base. The mausoleum is crowned by a massive dome. At the base of the dome elegant carved petals cover the drum. The exterior diameter is almost 133 feet (44 meters) and reaches a height of 90 feet (27. 4 meters) from a circular platform. Total exterior height from ground level is 198 feet (60 meters). The dome rests on a unique pendentive system. It is a system of intersecting arches that was not used anywhere else in India.
The only other commonly known instance was in the Great Mosque of Cordoba. The eight high pointed arches intersect in the interior of the cube at regular intervals and on their points rests the high circular platform with an opening of 96 feet (29. 5 meters) in diameter. The inner surface of the dome overlaps the edge of the circle by about 13 feet (four meters) so that part of the weight falls on the intersecting arches that bear and neutralize any other exterior forces. The dome is built of horizontal courses of brick with a flat section at its crown. It is cemented with lime and reaches a thickness of 12 feet (3. meters).
There are six openings at its base. An interesting discovery was made in the basement of a very strong circular foundation that matched the circular opening of the dome above. It, however, supports only a platform and a light wooden pavilion. One explanation could be that the original plan may have been based on the conventional mausoleum plan of a small domed chamber surrounded by an open arcade and that it was not until the foundation had been completed that the king or architect thought of resting the dome upon the outer walls, thereby enlarging the volume of dome several times.
Another interesting feature of the mausoleum is the gallery around the base of the dome that hangs out about 11 feet (3. 54 meters). It is accessed through the winding staircase in the four towers. It is known as the whispering gallery because the sound reflections from the dome allow the slightest of whisper can be heard even when standing cross the dome from each other. This mausoleum is one of the Bijapur's main architectural treasures.
Despite its incomplete condition, the sheer majesty of the structure renders visitors awestruck. The towers with their hemispherical domes, the carved petal borders and parapet give the building an exoticism that blends with monumentality and prevents this building from becoming just another building emulating classic Mughal architecture. A building that inspires admiration for its boldness would most definitely have been a spectacular experiment in completion.