The roof pavilions are small structures that fill the top of the pishtaqs on top of Humayun's Tomb. They can only be accessed from the roof terrace. These pavilions contain staircases for accessing the blue-domed chattris. The shaded gathering areas on the roof terrace were very likely to have been used as part of a madrasa. A madrasa is a "school for religious instruction, a college."1
1. Catherine Asher, The Architecture of Mughal India (Cambridge: Cambridge University Press, 1992), xxvii.
Tappin, Stuart. "The Structural Development of Masonry Domes in India." In Proceedings of the First International Congress on Construction History, Madrid, 20th-24th January 2003, edited by S. Huesta, 1941-52. Madrid: I. Juan de Herrera, SEdHC, ETSAM, A. E. Benvenuto, COAM, F. Dragados, 2003.