The Shah Jahan Mosque is one of the finest examples of Mughal architecture in South Asia — a large, harmonious building covered in blue and white glazed tile work that has given it the nickname the "Blue Mosque of Thatta." Construction began in 1644 on Shah Jahan's commission and the complex took several decades to complete, but the quality of workmanship throughout is extraordinarily consistent.
The mosque's defining feature is not its visual beauty, remarkable as that is, but its acoustic system. The building contains 93 domes of varying sizes arranged in a precise geometric pattern. The relationship between the domes creates a system of acoustic resonance such that a person speaking at the mihrab (prayer niche) can be heard clearly anywhere in the prayer hall — an effect that allowed the imam's voice to reach the entire congregation in an era before amplification. Engineers who have studied the mosque believe the acoustic design was deliberate and sophisticated, based on an understanding of sound propagation that is not fully understood today.
The tilework is in the Sindhi style — large areas of deep blue and turquoise, geometric and floral patterns, and the occasional calligraphic inscription. The effect is cooler and less restrained than comparable Lahore mosques. The mosque is still in active use; visitors should dress conservatively and remove shoes before entering.
A UNESCO World Heritage Site designation covers the mosque as part of the broader Thatta historic district.