Nagina Masjid, Marble mosque in Agra Fort, India.

Nagina Masjid is a private marble mosque within Agra Fort featuring three domes and intricate architectural details throughout. The interior prayer hall is divided into three sections by pillars and arches, with the central arch decorated with nine ornamental cusps.

Shah Jahan built the Nagina Masjid between 1631 and 1640 for his own use and that of the royal women. It was among the last structures added to Agra Fort before the emperor moved his capital to Shahjahanabad (Old Delhi) in 1648, after which the fort ceased to be the primary seat of power. The mosque is now a Monument of National Importance administered by the Archaeological Survey of India.

The name Nagina means "jewel" or "gem", and the mosque is also called the Gem Mosque or Jewel Mosque. It served Shah Jahan and the royal women, who could shop at the Mina Bazar below from the mosque's balcony without leaving purdah.

The mosque is located within Agra Fort and accessible during standard fort visiting hours without any additional entrance fee. The pathways to this space are well marked, and you can easily visit it while walking through the fort complex.

A balcony next to the mosque allowed royal women to watch and use the Mina Bazaar below while keeping their privacy. This clever architectural design served two different needs at once.