From the literal meaning of the word ‘rajbibi’ (royal lady), it can be presumed that this mosque was built at Gaur-Chapainawabganj by an influential family member of the ruler. The time of founding cannot be ascertained as no inscription has been assigned.
According to S M Hasan, “it may be placed between the early Ilyas Shahi period and the Husayn Shahi period, that is, during the restored Ilyas Shahi dynasty which ruled from 841/1437 to 892/1487”.
This small mosque lies on the western side of the tank -- Khania Dighi. The orientation of this tank towards east-west proves that it was dug by a Muslim ruler. The mosque belongs to the group of a square-shaped plan with a fore-room.
The old photograph of the mosque shows that the outer surface, the fore-room, and the corner turrets had fallen down. It was reconstructed by the Directorate of Archaeology of Bangladesh in 1990. The mosque measures externally -- 17.78m by 13.05m and internally, the prayer hall is 8.85m square with a 2.67m wide fore-room.
There are three arched openings in the east facade and one at each side of the fore-room. The main hall is accessed by three openings from the fore-room and has one opening at each of the north and south side.
Corresponding to the eastern openings, there are three Mihrab niches in the Qibla wall. Each of these Mihrab niches, contained within a rectangular frame, is arched with multi-foil cusps in the face. The outside of the Qibla wall shows a projection of the main Mihrab niche.
All the walls are brick-built with a stone layer at the plinth level and another stone layer in the lintel level. At the time of reconstruction, a stone layer was introduced in the mid-level of all the corner turrets. Only the Qibla wall is faced with stones from within.
There are six octagonal turrets at the corners: four at the corner of the main hall and two in the fore-room. These turrets have brick moldings at the base impressed with terracotta lozenge and the interspaces are embellished with terracotta frieze.
The main prayer hall is roofed over by a semicircular dome. The shoulder of the dome is decorated with merlon and projected moldings from within. The extrados of this dome is restored as a smooth surface, but after showing the different examples in Gaur and the photographs before restoration, it can be assumed that the extrados of the dome had a series of bands.
The fore room is divided into three unequal bays by two lateral arches running from the east to the west wall. Theses arches are also supported by stone pilasters engaged in the corresponding walls. The roof of the ruined fore room is rebuilt by the restorer with three small domes, but there is a doubt whether the middle part of the fore room was covered with a semicircular dome.
In the old photographs, the pendentives on both side-domes are clearly visible, but the central area has no evidence of such pendentives. Besides, the central bay is rectangular and wider than the flanking units. Hence, we can assume that the central rectangular area of the fore-room was most likely covered by a Chauchala vault like the Latton mosque at Gaur.
The exterior facades are richly decorated and marked by two rows of rectangular panels. Each of these panels is embellished with a cusped arch on pillars framing a typical chain and bell motif within. The upper part or cornice on all four sides is gently curved.
There are three moldings in this cornice impressed with ornaments. The interspaces between the moldings are also ornamented with continuous floral motifs. At the bottom is a necklace and tassel design, in the middle, a jail pattern, and in the topmost, a pattern of arched niches filled in with rosettes.
Prof Abu Sayeed M Ahmed is the Dean at the Department of Architecture at the University of Asia Pacific.