The Jamaat Khana Masjid, also known as the Khilji Mosque, is a historic mosque built by Khizr Khan, the son of Sultan Alauddin Khilji, between 1315-1325 AD. Located in the Nizamuddin Auliya Shrine Complex of Delhi, it is the largest structure within the complex and continues to be a place of worship. The mosque is distinguished by its red sandstone construction, featuring a central domed chamber flanked by two side chambers. Its walls are adorned with inscriptions of Quranic texts, and the arches are embellished with lotus bud motifs. The mosque underwent extensive conservation work by the Aga Khan Trust for Culture, which restored its original glory after years of deterioration. This restoration work included removing layers of paint to reveal the original sandstone and intricate geometrical motifs.